The fraction of cobalt-60 atoms remaining after 26.5 years is approximately 0.25 (1/4).
What is atom?An atom is the smallest unit of matter that still retains its properties. It consists of a nucleus, which is made up of protons and neutrons, surrounded by electrons that orbit the nucleus. Atoms are the building blocks of all matter and can combine to form molecules. Atoms are also constantly in motion and can be found in everything from air to rocks. They are essential for life, as they make up all the molecules that form the cells and organs in the human body.
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how does the hybridization of the sulfur atom change in the series SF2, SF4, SF6?
O sp, sp^3, sp^3 d^2 O sp^3, sp^3 d^2, sp^3 d^2 O sp^3, sp^3, sp^3 d^2 O sp, sp^3 d, sp^3 d^2 O sp^3, sp^3 d, sp^3 d^2
the hybridization of the sulfur atom change in the series SF2, SF4, SF6-Option 1 - sp, sp^3, sp^3 d^2 O sp^3, sp^3 d^2
The hybridization of the sulfur atom changes in the series SF2, SF4, SF6 as follows:
In SF2, the sulfur atom is in the sp hybridized state, meaning it has one s and one p orbital in its valence shell. This allows the sulfur to form a double bond with one fluorine atom.In SF4, the sulfur atom is sp3 hybridized, which means it has one s and three p orbitals in its valence shell. This allows the sulfur to form four single bonds with four fluorine atoms.In SF6, the sulfur atom is sp3d2 hybridized, which means it has one s, three p, and two d orbitals in its valence shell. This allows the sulfur to form six single bonds with six fluorine atoms.It is worth noting that the hybridization of the sulfur atom in SF6 is not very common and it is more likely the octahedral electron pair geometry of SF6 is achieved by the d orbitals of sulfur being empty and the sulfur atom being sp3 hybridized. In summary, the hybridization of sulfur in SF2 is sp, in SF4 is sp3, and in SF6 is sp3d2.
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How many mole is 1g?
One gram of a chemical is equivalent to one mole.
A physical characteristic called the molar mass is calculated by dividing the mass of a given substance by the substance's volume. The standard relative atomic mass of an element is multiplied by the molar mass constant, 1 × 10⁻³ kg/mol = 1 g/mol, to determine the molar mass of its atoms. A compound's molar mass is calculated by adding the standard atomic weights of the constituent atoms and multiplying the result by the molar mass constant.
One atom or molecule has the same mass in grams as one mole of a substance does in atomic mass units.
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how many grams of KNO3 that should be placed in the airbag to fully react with the Na.
10 Na + 2KNO3 > 1K20 + 5Na2O + 1 N2 (g)
P4(s) + Cl₂(g) → PCI3(l) + energy 4. Calculate the gram-formula mass of the product. Show all work. g/mol
The gram formula mass of the product, PCl₃, is 137.5 g.
What is the gram formula mass of a compound?The amount of a compound that has the same mass in grams as the formula mass in an atomic mass unit is said to have the compound's gram formula mass. It is also known as the molar mass.
Every element's atom has a characteristic mass, and each compound's molecule has a characteristic mass determined by the compound's formula.
The gram formula mass of the product PCl₃ is calculated below:
The atomic mass of P = 31 g
The atomic mass of Cl = 35.5 g
The gram formula mass of PCl₃ = 31 + 35.5 * 3
The gram formula mass of PCl₃ = 137.5 g
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A 25.0 mL sample of a saturated Ca(OH)2 solution is titrated with 0.028 M HCl, and the equivalence point is reached after 38.1 mL of titrant are dispensed. Based on this data, what is the concentration (M) of the hydroxide ion
The concentration of hydroxide ions in the solution is 0.0428 M.
Ions are what?A molecule or atom that has a net electrical charge is called an ion.
The balanced equation for the reaction between HCl and Ca(OH)2 is:
Ca(OH)2 + 2HCl -> CaCl2 + 2H2O
The number of moles of HCl added at the equivalence point can be found by multiplying the volume of HCl added (in liters) by its concentration in moles/liter:
moles HCl = (38.1 mL HCl x 0.028 mol/L HCl) / 1000 mL/L = 0.00107 mol HCl
The concentration of hydroxide ions can be found by dividing the number of moles of hydroxide ions by the volume of the solution:
[OH-] = moles OH- / L of solution
We know that the number of moles of HCl added is equal to the number of moles of OH- present, so:
[OH-] = 0.00107 mol OH- / (25.0 mL / 1000 mL/L) = 0.0428 M
Therefore, the concentration of hydroxide ions in the solution is 0.0428 M.
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what is the magnetic field due to the wire at the location of the electron?
The trick with this type of problem is that they usually don't tell you anything because they don't seem to have enough information. But the key is in the phrase "parallel to the wire".
A charged particle in a field should normally bend. If not, there must be some other force at work that balances the magnetic force. In this case it is the electron attraction.
Therefore, the magnetic force on the electrons must be "upwards" (i.e., the electrons are supposed to be downwards, hence towards the wire). Also, its size must be equal to mg of electrons (its mass is easy to find).
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How can you tell which metal is more reactive?
The reactivity of metals depends upon their position in the periodic table and their nature of undergoing chemical reactions.
The primary difference between metals is the ease with which they undergo chemical reactions. The elements toward the bottom left corner of the periodic table are the metals that are the most active in the sense of being the most reactive. Such as alkali metals like Lithium, sodium, and potassium all react with water, thus they are reactive in nature than the metals belonging to alkaline earth metals. The nature of more reactivity of alkali metals is due to larger atomic radius and low ionization energies and they have only one valence electron in its outermost shell.
Thus, the reactivity of metals depends upon their position in the periodic table and their nature of undergoing chemical reactions.
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The solid has a mass of 180 g. What is the density of the solid? Show your work. Be sure to use correct units of measurement. HELP NEEDED ASAP!!!!
Answer:
I'm telling the teacher on u man stop cheatingHow many moles are there in 10g?
Answer:
0.25 moles
Explanation:
In a random sample of 70 people, it was found that 44 of them were fans of the New York Yankees. What is the margin of error for the true proportion of all individuals who are fans of the New York Yankees?
A.
0.0088
B.
0.058
C.
0.063
D.
0.116
E.
0.173
The margin error of the population is 0.058. Option B
What is the margin of error?We know that the margin of error has to do with the allowance that has been given to accommodate the mistakes that can occur in a study. Let us note that the mistakes in the study may arise from a number of factors. One of the factors that could lead to the existence of error in the results of a study is a mistake when we reread off the values that we obtain from the study.
As such, we have;
M = √[p(1 - p)/n]
where:
p = sample proportion
n = sample size
We are given;
p = 44/70 = 0.6286
n = 70
Thus;
M = √[0.6286(1 - 0.6286)/70]
M = √0.003335172
M ≈ 0.058
This is now the margin of the error that we have in the study that has been done here.
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The following reaction occurred when a strip of aluminum was placed in a nickel solution. Which half-reaction represents the oxidation that has occurred in the reaction?
The reaction that shows oxidation is the one that has been shown in option D.
What is oxidation?We have to know that the process that we call oxidation would have to do with the loss of the electrons that we have in a system. If we are dealing with a neutral atom that has been oxidized then we would see an increase in the oxidation number of the atom. This same effect would be seen if we are looking at the oxidation of any other chemical specie that is under consideration.
Ni lost and electronNi^2+ was formedA total of two electrons were lost in the process.We need to look at the reactions that have been shown in the options that we have and then compare it with the overall redox reaction equation that we see at it has been shown in the reaction that has been attached to the question that we have in the attachment that is shown above here.
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A principle of value stream mapping is to concentrate on speeding up value-added operations.
True/False
False. Value streaming mapping technique is used to analyze the flow of information, people and material required to bring a product to a consumer.
The value stream mapping is a series of steps. Value stream mapping provides a structured visualization of the key steps and corresponding data needed to understand and intelligently make improvements that optimize the entire process. Value stream is a series of steps that occur to provide the product or service that customers wants. Value stream mapping enables us to understand where the value is added, where it’s not and more importantly, how to improve upon the collective process.
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Which is the best way to prepare 3-methoxypentane via the Williamson method? ( please explain why)
A). CH3OH + CH3CH2CHOHCH2CH3 + H2SO4, 140'C
B). CH3OH + (CH3)2 CHCH2CH2OH+ H2SO4, 140' C
C). CH3ONa + (CH3CH2)2CHBr
D). CH3 I + (CH3CH2)2CHONa
The best way to prepare 3-methoxypentane via the Williamson method is : D). CH3 I + (CH3CH2)2CHONa.
What is Williamson method?The most used technique for making ethers is the Williamson ether synthesis. A metal alkoxide displaces a halide ion from an alkyl halide in an SN2 reaction, which is how it happens. An alcohol and a potent base, such as sodium hydride, react to form the alkoxide ion.
Williamson synthesis is employed in the creation of both simple and mixed ethers. Alcoholic sodium or potassium alkoxide is heated with alkyl halide to create the appropriate ethers. ROR+NaX ROR+ONa+X. Methyl iodide produces dimethyl ether when heated in the presence of alcoholic sodium methoxide.
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How can light help us understand atoms?
Answer: We can calculate the energy levels of an atom
Explanation:
Spectral lines tell us how many different energy levels an atom has, and how far apart those energy levels are spaced.This is possible because spectral lines are the result of an excess (emission lines) or deficiency (absorption lines) of observed photons emitted from certain types of matter. The lines are caused by electrons moving between energy levels within individual atoms. Since each element emits it's own unique spectrum, this means that different types of atoms must have a distinct number of electrons in very particular energy levels.
A 70g chunk of metal at 180C was dropped in a bucket containing 400g of water at 25C. The final temperature of the mixture was 28C. What is the specific heat capacity of the metal
Thus, the metal has a mhm specific heat capacity of 2.472 Joel program degrees Celsius.
To calculate the temperature change (T), subtract the end temperature from the initial temperature. Multiply the temperature change by the sample's mass. Share the product's energy and heat output. The equation is C = Q / (T m). The amount of heat energy per unit mass needed to raise the temperature by one degree Celsius is known as the specific heat. The form given below, where c is the specific heat, is typically used to express the relationship between heat and temperature change. Let S represent the water's specific heat capacity. Consequently, the combined temperature of 50g of water at 20°C and 50g of water.
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How many moles are in 4.0 x 10^24 atoms of silicon?
Atoms of silicon have 0.15 moles.
[tex]4.0 × 10^2^4[/tex] atoms of silicon.
We have to find the number of moles.
Silicon has the atomic number 14.
One mole of silicon contains [tex]6.023× 10^2^3[/tex] atoms.
[tex]6.023× 10^2^3[/tex]number of atoms are present in one mole of silicon.
[tex]4.0*10^24[/tex]number of atoms will have-
[tex]6.023*10^2^3/4.0*10^2^4=0.15[/tex] moles.
Thus atoms of silicon have 0.15 moles.
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What is the molecular formula of a compound that has an empirical formula of CH2O and a molar mass of 120.12 g/mol
The molecular formula of a compound that has an empirical formula of CH₂O and a molar mass of 120.12 g/mol is C₄H₈O₄.
A molecular formula shows the number of different types of atoms that are present in a molecule whereas an empirical formula represents the simplest whole number ratio of the different atoms present in a molecule.
Given,
empirical formula= CH₂O
molar mass = 120.12 g/mol
To find: molecular formula
we know that,
atomic mass of carbon= 12 g/mol
atomic mass of hydrogen= 1g/mol
atomic mass of oxygen= 16 g/mol
molar mass of CH₂O
= (12+ 1×2 + 16) g/mol
=30 g/mol
therefore, molecular formula
⇒(CH₂O )n = 120.12
⇒30 n= 120.12
⇒n=120.12/30
⇒n= 4.004
⇒n≈4
Thus,
(CH₂O )n = (CH₂O )4 =C₄H₈O₄
Hence, molecular formula is C₄H₈O₄
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Select the correct answer. convection is a mode of heat transfer for which types of objects?
a. solids and liquids
b. gases and solids
c. gases only
d. liquids and gases e. liquids only
a). Convection is a mode or process of heat transfer for solids and liquids.
Convection is a process of heat transfer that occurs through the movement of fluids. It is the main mode of heat transfer in liquids and gases and is commonly used to transfer heat between two solid objects.
During convection, heat is transferred by the movement of particles or molecules in the fluid. The heat is transferred by the interaction of the particles or molecules with each other and the objects they come into contact with.
The particles or molecules that are hotter will transfer energy to the particles or molecules that are cooler. This causes the cooler particles or molecules to become hotter, resulting in heat transfer from one object to the other.
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How many moles of CH3CH2OH are contained in 548 mL of 0.0788 M CH3CH2OH solution?
0.0432 moles of CH3CH2OH are contained in 548 mL of a 0.0788 M CH3CH2OH solution.
what is molarity?Molarity is a unit of concentration that expresses the amount of solute in a solution in terms of moles of solute per liter of solvent. It is represented by the symbol M. It is calculated by dividing the number of moles of solute by the number of liters of solvent in the solution. For example, a 0.5 M solution of NaCl would contain 0.5 moles of NaCl dissolved in every liter of water.
To determine the number of moles of a solute in a solution, you can use the formula: moles = (concentration (M) x liters of solution).
In this case, the concentration of the CH3CH2OH solution is given as 0.0788 M and the volume is given as 548 mL. Converting mL to L by multiplying it by 10^-3, we get 0.548 L. By applying the formula, moles = 0.0788 M x 0.548 L = 0.0432 moles of CH3CH2OH.
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What causes pressure inside a helium balloon?
OA. The helium atoms exert an electrostatic force that pushes the
surface outward.
OB. The helium atoms expand and press on the surface of the balloon.
OC. The helium atoms bounce off the surface as they move inside the
balloon.
OD. The helium atoms stick to the surface of the balloon and increase
its weight.
Pressure inside a helium balloon: The helium atoms expand and press on the surface of the balloon.
What is helium balloon?Helium balloons are a type of balloon filled with helium gas. Helium is a light, non-flammable, inert gas that is found in abundance in the atmosphere and is used to inflate balloons. Helium balloons are often used in decorations, promotions, special events, parties, and displays. They come in a variety of shapes, sizes, and colors, and can be filled with helium and released into the atmosphere, creating a festive atmosphere. Helium balloons are also used in scientific experiments, such as measuring wind speeds, studying atmospheric pressure and air movement, and measuring the temperature of the atmosphere.
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15) Lidocaine 2 gm/500 mL D5W is ordered to run at 3.5 mg/min. At what rate should the IV pump be set
Ordered to run at 3.5 mg/min is a dose of lidocaine 2 g/500 mL D5W. The IV pump should be set at a rate of 52.5 mL per hour.
Given 1mg/min = 60mg/hour
Then 3.5 mg/min = 3.5 x 60 mg/hour = 210mg/hour
Lidocaine is 2gm/500mL = 2000mg/500mL
If you only need to calculate the infusion rate, or the amount of medication to infuse per hour, you can do it by taking the entire volume in mL and dividing it by the total number of hours the medication is supposed to be infused over. This will give you the rate in mL per hour.
Then the flow of rate = 210mg/hour / 2000mg/500mL = 210x500/2000 = 52.5mL/hour.
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What is the relationship between CO2 and O2 for sea urchins?
The relation between CO₂ and O₂ for sea urchins is impacted by the rise in carbon dioxide and oxygen is absorbed from the water.
The exoskeleton of sea urchins, which are found in the ocean, is comprised of calcium carbonate. They create calcium carbonate by absorbing the carbon dioxide from the water. As waste, they discharge carbon dioxide out of the anus.
The sea urchin takes its oxygen from the water. In the canals, oxygen diffuses. Oxygen diffuses into the cells from canals. The ocean's pH may rise as a result of the increased carbon dioxide. A higher pH has a deleterious impact on the calcification process. Therefore, the increased carbon dioxide has an impact on how the larvae and adults of sea urchins calcify.
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What is called proton number?
Proton number is called atomic number.
The chemical element's atomic number, also referred to as the nuclear charge number, is determined by the charge number of an atomic nucleus. This is the quantity of protons in the nucleus of each of that element's atoms. The atomic number refers to the number of protons in the nucleus of an atom. The amount of protons in an element determines what kind of element it is.
Both protons and electrons are equal in number in a neutral atom. The mass of an atom, represented by the letter M, is equal to the total of its protons and neutrons in the nucleus.
The number of protons in the atom's nucleus is therefore equal to the atomic number (Z). in an uncharged atom.
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Convert the following numbers into the standard form of scientific notation 0. 010x 10e5
The standard form of scientific notation for 0. 010x 10e5 is 1.0 × 10^3.
Scientific notation is a form of presenting large numbers or very small numbers in a simpler form.
There are some rules to write scientific notation:
The base should be always 10. The exponent must be a non-zero integer.
Absolute value of the coefficient should be greater than or equal to 1 but it should be less than 10.The mantissa carries the rest of the significant digits of the number.
The power of 10 will be positive, if the given number is multiples of 10 then the decimal point has to move to the left. The power of 10 will be negative If the given number is smaller than 1 and then the decimal point has to move to the right.
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Which is true of an atom? A. The valence electrons make up the majority of the mass and volume of an atom. B. The electron cloud makes up the majority of the mass and volume of an atom. C. The valence electrons make up the majority of the mass of an atom but do not take up much volume. D. The electron cloud makes up the majority of the volume of an atom but does not have much mass
The statement that is true about an atom is D. The majority of volume of an atom is make up by the electron cloud which has no mass.
In an atom, there are three sub-atomic particles that are protons, electrons and neutrons. The protons and neutrons are present inside the nucleus while the electrons revolve around the orbits i.e., circular orbits. The majority of volume of an atom is make up by the electron cloud which has no mass. Electrons are negatively charged in nature while the positive species are protons and neutrons carry no charge in them. The circular path is termed as orbits in which electrons revolve.
Thus, option D is the correct choice.
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What is the molecular formula of a compound whose empirical formula is CH4 and has a molar mass is 32. 086 g/mole?
The molecular formula of a compound whose empirical formula is CH4 and has a molar mass is 32. 086 g/mole is C
The molecular formula of a compound is the actual number and types of atoms that make up a molecule. It gives the exact number of atoms of each element in a molecule.
On the other hand, the empirical formula of a compound represents the simplest whole number ratio of atoms that make up a compound. It gives the lowest whole number ratio of atoms of each element in a molecule.
Multiply the subscripts in the empirical formula by a factor needed to reach the molar mass of the compound. In this case, CH4 has a molar mass of 16.04 g/mol and the compound has a molar mass of 32.086 g/mol.
32.086 g/mol/16.04 = 2
Multiplying the subscripts by 2, the molecular formula of the compound is C2H8.
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Early chemists, known at the time as alchemists, had a difficult time understanding the Law of Conservation of Mass. Using the burning of wood as an example, what property of matter made this law difficult for early scientists to understand?
Different types of wood burned differently.
Wood is heavier than ash.
The fire was too bright to observe the reaction.
The gases produced escaped to the atmosphere.
Answer:
The gases produced escaped to the atmosphere.
A compound is found to contain 10.37 % phosphorus, 4.689 % nitrogen, and 84.95 % iodine by weight. The molecular weight for this compound is 298.8 g/mol. What is the molecular formula for this compound
Answer:
P₂N₂I₄
Explanation:
Firstly, we calculate the empirical formula of the compound. To do this we find the moles of each element. Treat the percentages as masses.
The formula for moles is:
[tex]moles = \frac{mass}{relative \: atomic \: mass}[/tex]
The masses of each element are:
Phosphorus = 10.37g
Nitrogen = 4.689g
Iodine = 84.95g
The relative atomic masses of each element are:
Phosphorus = 31.0
Nitrogen = 14.0
Iodine = 126.9
Using these values, we can calculate the moles of each element:
[tex]moles \: of \: phosphorus = \frac{10.37}{31.0} = 0.335[/tex]
[tex]moles \: of \: nitrogen \: = \: \frac{4.689}{14.0} = 0.335[/tex]
[tex]moles \: of \: iodine \: = \: \frac{84.95}{126.9} = 0.669[/tex]
Using the moles, write them in a ratio to find the ratio of moles:
Phosphorus : nitrogen: iodine
0.335 : 0.335: 0.669
The smallest number here is 0.335, so divide each number by 0.335
0.335÷0.335=1
0.335÷0.335=1
0.669÷0.335=1.99... = 2 (round to the nearest whole number)
These numbers are used as the subscripts of each element.
This means that the empirical formula is:
PNI₂
To calculate the molecular formula:
[tex]\frac{molar \: mass \: of \: molecular \: formula}{molar \: mass \: of \: empirical \: formula}[/tex]
The molar mass of empirical formula is adding the molar masses of compound PNI2:
31.0 + 14.0 + 126.9 = 171.9
The molar mass of molecular weight or mass = 298.8 (given from the question)
Substitute these in the formula above:
[tex] \frac{298.8}{171.9} = 1.738...[/tex]
1.738 = 2 rounded to the nearest whole number.
Multiply all the subscripts seen in the empirical formula by the number 2:
PNI₂ × 2 = P₂N₂I₄
Liquid hexane CH3CH24CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 7.76 g of hexane is mixed with 34. g of oxygen. Calculate the minimum mass of hexane that could be left over by the chemical reaction. Round your answer to 2 significant digits.
the minimum mass of hexane that could be left over by the chemical reaction is 17.2 grams of.
Hexane, a non-polar solvent having a boiling point of 68 degrees Celsius, is the one used to extract the oil from rice bran to produce rice bran oil (RBO). The International System of Units uses the mole (symbol: mol) as the unit of material quantity. How many elementary entities of a particular substance are present in an object or sample is determined by the quantity of that material.
Hexane moles equal 29/86=0.34
41.3/32 = 1.30 moles of oxygen
One mole of hexane takes 9.5 moles of oxygen, as shown by the reaction.
In this case, oxygen is the limiting reagent.
Consumption of moles of hexane is 1.30/9=0.144
Hexane remaining in moles is equal to 0.20 to 0.34 moles.
Hexane mass remaining = 0.2*86=17.2 grams.
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legit need help asap
ignore the screenshot stuff
BUT LIKE
HELP
Answer:
a.LiF
b.BeO
c.MgF2
d.AlCl3
e.Be3N2
Explanation:
So, the main thing with chemical formulas is making sure that the cation and anion's charges will cancel out if you add the total sum of charges together.
For A, halogens only form -1 charge ions, so F will have to be F-. Lithium, being a group 1 element, will form an ion of Na+. Therefore, the formula is NaF.
For B, Beryllium is a Group 2 element that forms +2 charges, while Group 16 elements like O form -2 charges. Therefore, BeO would work as the sum of charges will equal zero.
For C, Magnesium is a Group 2 element, so it has a +2 ion, while fluorine is a halogen, so a -1 charge for the F- ion. So, you need two F- ions to balance out one Mg2+ ion. So, it is MgF2
For D, Aluminum is a Group 13 element, which can form +3 charges. Therefore, Al can form a +3 charge, so that means for Cl- (recall it is a halogen,) it needs three Cl- ions to cancel one Al3+ ion. So, it is AlCl3.
For E, Group 15 elements like N form -3 ions, so the ion for nitrogen is N3-. Beryllium is a Group 2 element, so it is Be2+. The common multiple of 3 and 2 is 6, so you need to find a way to have a +6 and -6 charge. So, three Be2+ ions (totaling a net charge of +6) need to cancel with two N3- ions (again a net charge of -6) to form the compound. Therefore, it is Be3N2.