Answer:
Since the noble gases are unreactive or inert, they are safe to use. Helium is used to fill balloons and airships, because it is much lighter that air and it will not catch fire. Neon is used in advertising signs. It will give red glow, but the color can be changes by mixing it with other gases.
Explanation:
Calculate the mass of 0.2 moles of zinc nitrate.
Answer:
mass = 37.8 g
Explanation:
mass = mol × molar mass
mol = 0.2
molar mass = Zn(NO3)2
Zn = 65
N = 14
O = 16
substitute the values into Zn(NO3)2
Zn(NO3)2
= 65+2[ 14+3(16) ]
= 65 + 2(62)
= 65 + 124
= 189 g/mol
mass
= mol × molar mass
= 0.2 mol × 189 g/mol
= 37.8 g
Neon is located in the last group of the periodic table. How many valence electrons
Answer:
8 valence electrons
Explanation:
Neon is a noble gas, and all noble gases have 8 valence electrons. The same goes for its group; all elements in the last group of the periodic table have a full valence shell--8 electrons.
An atom is
a. the smallest unit of matter that maintains its chemical identity.
b.the smallest unit of a compound.
c.always made of carbon.
d.smaller than an electron
Answer:
A. The smallest unit of matter.
Explanation:
Atoms make up everything and are the smallest unit of all units.
1)
v (m/s)
9.6
다
2.4
0
6.0
10.0
18.0 (5)
What two quantities must stay the same in order for an object to have a constant velocity?
A)
The speed and kinetic energy must be constant.
3
B)
The speed and mass of the object must be constant.
The speed and direction of travel must be constant.
D)
The force applied to and direction of travel must be constant.
Answer:
A
Explanation:
a is the right answer abi
state with reasons the most suitable methods for collecting hydrogen
Answer:
Upward delivery or downward displacement of air
Explanation:
The method of collection of a gas is dependent on it's density.
Gases that are less dense than air are collected by upward delivery or downward displacement of air while gases that are denser than air are collected by downward delivery or upward displacement of air.
Hydrogen is less dense than air hence it is collected by upward delivery or downward displacement of air.
EZ MODE -_- What could you do in an experiment to get more accurate results? Change two of your variables. Only make observations that involve sight. Only use new materials. Perform repeated trials
Answer:
they change the object hehehehe
Answer:
D. Perform repeated trials.
Explanation:
I did the exam and got it correct :D!
What mass of Ca(OH)2 would you need to make 300.0mL of a 1.2M solution of Ca(OH)2
Answer:
is there a picture.....????
Metals make what type of ions
Answer: Metal atoms lose the electron/ electrons in their highest energy level and become positively charged ions.
Answer:
Cations
Explanation:
Cations (positively-charged ions) and anions (negatively-charged ions) are formed when a metal loses electrons, and a nonmetal gains those electrons. The electrostatic attraction between the positives and negatives brings the particles together and creates an ionic compound, such as sodium chloride.
Key Terms:
➡An anion can be defined as an atom or molecule that is negatively charged. ➡A cation can be defined as an atom or molecule that is positively charged. ➡They have an opposite electrical charge, therefore they get attracted to each other.
All living organisms are composed of
OA. at least three cells.
ОВ.
one or more cells.
OC. at least 100 cells.
OD. only one cell.
Answer:
OB- one or more cells
Explanation:
hope this helps :)
Anna broke a test tube. She picked up the pieces of glass with one hand and placed them in her other hand.
Once she picked up all of the pieces, she placed them in the garbage can. What was not done correctly? What
should have been done instead?
Answer:
Tell the teacher and wait for it to be swept up.
How are plant and animal structures similar?
Answer:
I think they both need water and sun light to stay alive
Explanation: Animals need water so they can have energy and they have extra energy when they are in the sun they have more energy
ALUMINUM (AI)
+ NITRATE (NO3)
Answer:
Al(No3)3
Explanation:
hope this is correct....
⚠️HELP DUE IN 10 MINS WILL GIVE BRAINLIEST!!! THANKS⚠️
10 grams of calcium-37 remain after 700 milliseconds (0.700 seconds).
How much calcium was in the original sample?
Answer:
hahahh noob
Explanation:
what is a substrate
Answer:
a substrate is surface or material on or from an organism lives, grows, or obtains its nourishment.
Explanation:
Hey I hope this helps.....
identify the type and number of atoms in each molecule of the reactants and products.
CaCO3 -> CaO + CO2
Answer:
CaCO3: 1 calcium 1 carbon 3 oxygen
CaO: 1 calcium 1 oxygen
CO2: 1 carbon 2 oxygen
To see the number of atoms of any element in a particular molecule or compound, we need to multiply the stoichiometry that is written in front of the molecule to the number that is written on the foot of that element. The number of atoms of calcium, carbon and oxygen are 1, 1, 3.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
The balanced reaction is
[tex]CaCO_{3}\rightarrow CaO + CO_{2}[/tex]
There are three types of element present in this reaction: calcium, oxygen and carbon
Number of atoms of calcium on reactant and product side is 1
Number of atoms of carbon on reactant and product side is 1
Number of atoms of oxygen on reactant and product side is 3
Therefore, the number of atoms of calcium, carbon and oxygen are 1, 1, 3.
To know more about atom, here:
https://brainly.com/question/13518322
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A scientist is studying a protist and records the following information about it:Cell has a nucleus Has a flagella Produces oxygen Found in salt water Which conclusion is best supported by the information?A. B.The protist is an animal-like flagellate because it has a flagellum. C.The protist is a plant-like dinoflagellate because it produces oxygen.D.The protist is a plant-like dinoflagellate because it was found in salt water.The protist is an animal-like flagellate because it has a nucleus.
Answer:
B)The protist is a plant-like dinoflagellate because it produces oxygen.
Explanation:
This was the answer on edge nuity
The conclusion that is best supported by the information is that the protist is a plant-like dinoflagellate because it produces oxygen.
What is a protist?A protist is any eukaryotic organism that is, an organism whose cells contain a cell nucleus that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor,the exclusion of other eukaryotes means that protists do not form a natural group, or clade.
Therefore, some protists may be more closely related to animals, plants, or fungi than they are to other protists. However, like the groups algae, invertebrates, and protozoans, the biological category protist is used for convenience. Others classify any unicellular eukaryotic microorganism as a protist.The study of protists is termed protistology.
Learn more about protist,here:
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How is radiation different from conduction?
SELECT AN ANSWER
Radiation is the transfer of heat through molecular contact, and conduction is the transfer of energy by waves.
Radiation is the transfer of energy by waves, and conduction is the transfer of heat through contact with air.
Radiation is the transfer of energy by waves, and conduction is the transfer of heat through molecular contact.
Radiation is a type of heat transfer in the atmosphere as opposed to conduction, which does not transfer energy.
Answer:
Radiation is the transfer of energy by waves, and conduction is the transfer of heat through contact with air.
Explanation:
Conduction is the transfer of thermal energy through direct contact. Radiation is the transfer of thermal energy through thermal emission.
please help!!
How many moles of NO2 are equivalent to 74.3 grams of NO2?
(N = 14.01 g/mol, O = 16.00 g/mol)
Answer:
= 1.615 moles
Explanation:
I did it on a test and got it right
When a cold front is approaching, what happens?
Answer:There is colder and drier air coming
Explanation:
Answer:
Cold fronts generally move from northwest to southeast. The air behind a cold front is noticeably colder and drier than the air ahead of it. When a cold front passes through, temperatures can drop more than 15 degrees within the first hour.
Explanation:
Pretend you are visiting the equator and it is 12pm. When you look up at the sun, it is exactly over your head. You call a friend on the phone, and your friend says it is also 12pm at their house, but the Sun is not exactly overhead. It is actually a little lower in the sky. Are the longitude lines and latitude lines where you are the same as or different from the longitude lines and latitude lines where your friend is. How do you know?
Answer:
Different
Explanation:
Surely, the longitude lines and latitude lines where you are different from the longitude lines and latitude lines where your friend is. This is evident from the fact that sun's position in the sky is different at same time of the date. Your are the equator, then your friend must be above equator in northern hemisphere or below in southern hemisphere.
The enthalpy of combustion of octane is -5470 kJ/mol. Octane (formulae C8H18) was used to heat some water in a copper can. The amount of octane used up was 0.1 g. The amount of water in the can was 100 cm3 . a) Find the moles of octane which was used up. (Show calculations)
Answer: 0.0009 moles of octane were used up.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
Given mass of octane = 0.1 g
Molar mass of octane = 11.23 g/mol
Putting in the values we get:
[tex]\text{Moles of octane}=\frac{0.1g}{114.23g/mol}=0.0009moles[/tex]
Thus 0.0009 moles of octane were used up.
What happens to the pH of an acid when the solution is diluted by a factor of 10?
Answer:
Diluting an acid decreases the concentration of H+(aq) ions, which increases the pH level of the solution towards 7, making it less acidic.
Explanation:
However, the pH level of an acidic solution cannot become greater than 7, because the water you add to dilute it is not alkaline.
How many moles are in 825 atoms of carbon?
1.37 × 10⁻²¹ mol C
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
825 atoms C
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
[tex]\displaystyle 825 \ atoms \ C(\frac{1 \ mol \ C}{6.022 \cdot 10^{23} \ atoms \ C} )[/tex] = 1.36998 × 10⁻²¹ mol C
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
1.36998 × 10⁻²¹ mol C ≈ 1.37 × 10⁻²¹ mol C
Croquet balls must have a mass of 0.50 kg. A red croquet ball, moving at 10
m/s, strikes an at-rest green croquet ball head-on. The red ball continues
moving at 1.5 m/s after it hits the green ball. What is the final speed of the
green ball?
O A. 5 m/s
B. 8.5 m/s
C. 1.5 m/s
O D. 15 m/s
SUS
The final speed of the green ball : 8.5 m/s
Further explanationGiven
mass of Croquet ball = 0.5 kg
v₁= 10 m/s
v₁'= 1.5 m/s
Required
the final speed
Solution
The law of conservation of momentum
m₁v₁ + m₂v₂ = m₁v₁ '+ m₂v₂' (1=red croquet ball, 2=green croquet ball)
v₂=0 (at rest)
Input the value :
[tex]\tt 0.5\times 10+0.5\times 0=0.5\times 1.5+0.5\times v_2'\\\\5=0.75+0.5v_2\\\\4.25=0.5v_2\rightarrow v_2=8.5~m/s[/tex]
true or false: heat and pressure combine to form a volcanic eruption
Answer:
true hope that helps
Explanation:
Which of these is a characteristic of a radioactive nucleus?
Answer:
The Answer is option D
Explanation:
The nucleus of a radioactive element is unstable. The nucleus will break down over time, reducing the amount of the element remaining.
What is the coefficient of H2 when the following equation is correctly balanced? CO (g) + H2(g) → H20 (g) + CH4 (9)
Answer:
3. CO + 3H₂ ⇒ H₂O + CH₄
Explanation:
match reactants and products on both sides of the equation.
What is genetic mutation
Answer:
A gene mutation is a permanent alteration in the DNA sequence that makes up a gene, such that the sequence differs from what is found in most people.
write the relation between wavelength frequency and velocity for a sound wave
Explanation:
frequency; the no of round completed in one second is called frequencywavelength; the distance between two identical point on wave line velocity; the distance cover in one second is called velocityHelp!! 8th grade science (for a grade)
Answer:
I DONT GET IT IETHER
Explanation:
DONT GET IT