Answer:
B. The cells.
call
Cells are considered the basic units of life in part because they come in discrete and easily recognizable packages. That's because all cells are surrounded by a structure called the cell membrane — which, much like the walls of a house, serves as a clear boundary between the cell's internal and external environments.
how can a scientist make a solution using salt and water?
Answer:
by boiling water and add the salt
Explanation:
because salt dissolves better if mixed with hot water which makes the process faster and effective
In the context of a balanced chemical equation, a____is a number to the lower right of an element or ion within formula and it applies to____. A____is a number to the left of a formula and it applies to_____. Only_____should be added or changed when balancing chemical equations.
Answer:
Explanation:
The preceding chapter introduced the use of element symbols to represent individual atoms. When atoms gain or lose electrons to yield ions, or combine with other atoms to form molecules, their symbols are modified or combined to generate chemical formulas that appropriately represent these species. Extending this symbolism to represent both the identities and the relative quantities of substances undergoing a chemical (or physical) change involves writing and balancing a chemical equation. Consider as an example the reaction between one methane molecule (CH4) and two diatomic oxygen molecules (O2) to produce one carbon dioxide molecule (CO2) and two water molecules (H2O). The chemical equation representing this process is provided in the upper half of Figure 1, with space-filling molecular models shown in the lower half of the figure.
Psychology is the study of the human brain. A psychoanalyst is a person who
analyzes people's minds. What does the prefix psycho-mean?
A. Related to the brain
B. Related to studying
C. Related to science
D. Related to analysis
What is the charge that a Phosphorus atom would likely form?
+1
+2
+3
-1
-2
-3
Answer:(b) By referring to a periodic table or table of elements, we see that phosphorus (symbol P) has an atomic number of 15. Thus, each atom has 15 protons. The mass number of the ion is 15 + 16 = 31. Because the ion has 15 protons and 18 electrons (three more electrons than protons), its net charge is 3-
An unknown compound was found to be soluble in concentrated sulfuric acid; however, the 2,4-DNP, chromic acid, and potassium permanganate gave negative results. The only positive result detected was the ferrous hydroxide test. What is the most likely functional group present in such compound
Explanation:
2,4-DNP is negative: aldehyde and ketone absent
Chromic acid is negative: alcohol absent.
KMnO4 test negative: alkene absent
The only positive result is for Fe(OH)2.
Nitro group-containing compounds react with ferrous hydroxide to give amine and ferric hydroxide red ppt. Hence given compound contains the nitro group (-NO2).
160 mL of a 37.5 % (m/v) LiNO3 solution
Answer:
60g of LiNO3 are required
Explanation:
Calculate the amount of solute, in grams or milliliters, to prepare...
The percentage mass/volume %(m/v) is defined as the mass in grams of the solute in 100mL of solution
To solve this question we must know that in a 37.5% (m/v) of LiNO3 you have 37.5g of LiNO3 in 100mL of solution.
Thus, to prepare 160mL are required:
160mL * (37.5g / 100mL) =
60g of LiNO3 are requiredWhich of these is most likely made of pieces of rock that are weathered by water and wind?
O A diamonds
OB sand
OC grass
OD vegetables
Answer:
The answer would be sand.
Explanation:
Sand is weathered down tiny pieces of rock. Sand flows down rivers to shores and slowly builds up to form beaches.
Answer:
The Answer is gonna be B sand
Is vinegar and rubbing alcohol soluble or insoluble?
A watt is
A. 1 cal/s.
B. 1 joule/s.
C. 1 s/cal.
D. 1 s/joule.
Answer:
The answer would be B. 1 joule/s.
Explanation:
The answer is B because the power in general is normally defined as energy over time. Watts are defined as 1 Watt = 1 Joule per second (1W = 1 J/s) which means that 1 kW = 1000 J/s.
Another reason why it's B is because I had the same exact question in class, I took a screenshot of it a day ago:
Hope this helps
Pls help I need help ASAP!!! Be accurate
Using the weather radar map shown here, infer at which lettered point the most likely tornado formation and damage would
occur.
es )
A)
А
B)
B
C С
D
D
Answer:
c
Explanation:
this is because it makes sense
Answer:
d
Explanation:
Using the Lewis dot system, show the formation of a covalent bond between
A. Two Br atoms
B. A Br atom and a Cl atom
C. A N atom and three H atoms
D. A C atom and 4 Cl atoms
E. An S atom and 2 H atoms
How is water used in society
Answer:
Water can be used for direct and indirect purposes. Direct purposes include bathing, drinking, and cooking, while examples of indirect purposes are the use of water in processing wood to make paper and in producing steel for automobiles. The bulk of the world's water use is for agriculture, industry, and electricity.
Explanation:
Answer:
water is used for drinking, bathing, cooking, agriculture etc
Which one(s) are correct for ionic naming? Select all that apply.
O dicopper trichloride
O iron sulfide
O nickel Il carbonate
O strontium iodide
O carbon dioxide
What volume is occupied by 22.1 g of O2 at 52°C and a pressure of 1.63 atm?
the sum of two number is 50,and their difference is 30.find the sum
Answer:
40 and 10
Explanation:
40 plus 10 is 50 40 minus 10 is 30
Answer:
40 and 10
Explanation:
A mixture of 2.0 moles of H2, 2.0 moles of NH4, 4.0 moles of CO2, and 5.0 moles of
N2 exert a total pressure of 800 torr. What is the partial pressure of each gas in the
mixture respectively?
Answer:
0.01125
Explanation:
:b
(2pts) Post-lab Questions (1pts) 1. Do you expect the solubility of Borax to increase or decrease as temperature increases? Select the option that best explains why. Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger. Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get smaller. Solubility will decrease, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get smaller. Solubility will decrease, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger. Choose... (1pts) 2. Why was it necessary to make sure that some solid was present in the main solution before taking the samples to measure Ksp? Select the option that best explains why. To make sure no more sodium borate would dissolve in solution. To ensure the dissolution process was at equilibrium. To make sure the solution was saturated with sodium and borate ions. All of the above
Answer:
1. Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger.
2. To ensure the dissolution process was at equilibrium.
Explanation:
Given that;
ΔG°= -RTlnK
and
ΔG° = ΔH° - TΔS°
So;
-RTlnK = ΔH° - TΔS°
lnK = ΔH°/-RT - TΔS°/-RT
lnK = -(ΔH°/RT) + ΔS°/R
K = e^-(ΔH°/RT) + ΔS°/R
Hence, Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger.
2.
Since solubility is an equilibrium process, it means that some undissolved solute must be present in order to determine the solubility product correctly.
Solubility is the ability of the solute to dissolve in the solution. As temperature increases, the solubility increases, and the presence of solid ensure dissolution.
What is Gibbs energy?The Gibbs free energy is the change in the energy of a system from the energy present in the reactant towards the product formation.
It is given as,
[tex]\rm \Delta G^{\circ}= \rm -RTlnK \\\\\rm \Delta G ^{\circ} = \Delta H ^{\circ} - T\Delta S ^{\circ}[/tex]
Equating both equations we get:
[tex]\begin{aligned} \rm -RTlnK &= \rm \Delta H ^{\circ} - T\Delta S ^{\circ}\\\\\rm lnK &=\rm -(\dfrac{\Delta H ^{\circ}}{RT}) + \dfrac{\Delta S ^{\circ}}{R}\\\\\rm K &=\rm e^{-(\frac{\Delta H ^{\circ}}{RT}) + \frac{\Delta S ^{\circ}}{R}}\end{aligned}[/tex]
Thus, the solubility of the substance increases with an increase in temperature.
The solubility product is estimated correctly by the equilibrium process that ensures the presence of the undissolved solute particles.
Therefore, 1. option A. solubility increases and 2. option B. to ensure the equilibrium process are the correct options.
Learn more about solubility here:
https://brainly.com/question/14092287
1. When there is light, photosynthesis can
A. occur, in the chloroplast.
B. not occur, and the stomata will not be open.
C. not occur, and the stomata will be open.
D. occur, in the
mitochondria.
Answer:
A
Explanation:
Answer:
A. occur, in the chloroplast.
Explanation:
Photosynthesis occur in chloroplasts, with the help of sunlight. Where mitochondria help in respiration
Which one is not soluble in water Licl, lioh or li3po4
Answer:
li3po4
Explanation:
When 3.52 g of bismuth oxide (molar mass - 465.96 g/ml) reacts with excess carbon to form 2.91 g of bismuth metal (molar mass-208.98) according to the equation:
Bi2O3(s) + 3C(s) = 2 Bi(s) + 3 CO(g)
24
What is the percent yield of the reaction?
(Answer to 1 decimal place)
25
the first three process involved in water purification can be summarize as
Answer:
Aeration,flocculation,coagulation.
Explanation:
Answer:
.
Explanation:
Lion 7
Which of the following is a valid science lab safety guideline?
omplete
s out of
Select one:
O a. Do not eat or drink anything while in the lab.
ag
tion
O b. Wear a drawstring hoodie to protect yourself from chemicals.
O c. Wait to clean up any spills until you complete the lab
procedure.
O d. Change the lab procedure if necessary to improve the
experiment.
Check
Answer:
A.
Explanation:
You should NEVER eat or drink anything in a lab area. You never know what chemicals or gases are in the lab, and they can harm you.
Wearing a drawstring hoodie won't protect you from chemicals.
Don't wait to clean up chemicals, immediately get a teacher and clean it up (follow the teachers instructions). You never know what has spilled, and if it is harmful or not, or if there is a certain procedure to clean it up.
Don't change the equipment in the middle of an experiment. This can tamper with your results, and depending on what you are working with, this can be dangerous.
Which of the following molecules has a bent shape?
O A. CO2
O B. H20
O C. BeCl2
O D. NH3
Question 3
Which of the objects on the shelf has the greatest inertia?
10 kg
5 kg
2kg
a
b
2 kg
5 kg
10 kg
С
d
The all have the same inertia
A chemist weighed out 7.22 g of silver. Calculate the number of moles of silver she weighed out.
Be sure your answer has the correct number of significant digits.
Answer:
0.067 mole Ag°
Explanation:
Given 7.22 g Ag° = 7.22g Ag/ 107.8g/mol = 0.0670 mole Ag° (3 sig. figs.)
2. Given the following equation: 2 KCIO3 ---> 2 KCl + 3 O2
How many moles of O2 can be produced by letting 12.00 moles of KClO3 react?
show work. helppp asap
Answer:
18 moles of O2 can be produced by letting 12.00 moles of KClO3 react
Explanation:
The balanced equation is
2KCIO3 ---> 2 KCl + 3 O2
As per the reaction,
2 mole of KClO3 produces 3 mole of O2 gas
Hence, 12 moles of KClO3 will produce [tex]12*\frac{3}{2} =18[/tex]
Hence, 18 moles of O2 can be produced by letting 12.00 moles of KClO3 react
What is the molarity of a 250ml KCl solution made by diluting 175mL of a 3.00 M solution?
Answer:
2.1 M
Explanation:
The dilution equation is [tex]M_{s} V_{s} = M_{d} V_{d}[/tex].
[tex]M_{s}[/tex] = the molarity of the sock solution
[tex]V_{s}[/tex] = the volume of the sock solution
[tex]M_{d}[/tex] = the molarity of the diluted solution
[tex]V_{d}[/tex] = the volume of the diluted solution
The stock solution would be what is doing the diluting, so "175 mL of a 3.00 M solution". So [tex]M_{s}[/tex] = 3.00 M. Then: Converting 175 mL to liters: [tex]175 mL * \frac{1 L}{1000mL} = 0.175 L[/tex] (This is [tex]V_{s}[/tex])
And converting 250 mL KCl to liters: [tex]250 mL * \frac{1 L}{1000mL} = 0.250 L[/tex] (This will be [tex]V_{d}[/tex])
Then, we plug in our given into the dilution equation, resulting in:
[tex]3.00 M * 0.175 L = M_{d} * 0.250 L[/tex] (divide both sides by 0.250 L, in order to get [tex]M_{d}[/tex] by itself)
[tex]\frac{3.00 M * 0.175 L}{0.250 L} = M_{d}[/tex]
[tex]M_{d} = 2.1 M[/tex]
So, the molarity of 250 mL KCl made by diluting 175 mL of a 3.0 M solution would be 2.1 M (mol/L).
Hopefully this helped you understand the topic a little bit better. I just finished molarity and dilutions in Chemistry last week. Good luck!
PLEASE HELPP!
a 55g block of metal has a specific heat of 0.45 J/g°C. What will be the temperature change of this metal if 450 J of heat energy are added?
Answer:
18.18 C
Explanation:
m=55
C=0.45
Q=450zj
ch.temp=?
Q=mct
450 = (55)(.45)T
450 = 24.75
/24.75 = /24.75 (cancels out)
18.18 is the answer
Worth 100 points plus ill mark brainliest
How many grams of sodium phosphate ( Na₃PO₄ )are required to make 125 milliliters of a 0.240 Molar solution?
4.92
6.48
8.44
12.5
Answer:
4.92 grams of sodium phosphate (Na₃PO₄) are required to make 125 milliliters of a 0.240 M.
Explanation:
Molarity is a measure of concentration that indicates the number of moles of solute that are dissolved in a given volume.
The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:
[tex]Molarity=\frac{number of moles}{volume}[/tex]
Molarity is expressed in units [tex]\frac{moles}{liter}[/tex].
In this case:
Molarity= 0.240 Mnumber of moles= ?volume= 125 mL= 0.125 LReplacing in the definition of molarity:
[tex]0.240 M=\frac{number of moles}{0.125 L}[/tex]
Solving:
number of moles= 0.240 M*0.125 L
number of moles= 0.03 moles
Being the molar mass of sodium phosphate 164 g/mole, that is, the mass of one mole of the compound, you can calculate the mass of 0.03 moles using the following rule of three: if 1 mole of the compound has 164 grams, 0.03 moles contains how much mass?
[tex]mass=\frac{0.03 moles*164 grams}{1 mole}[/tex]
mass= 4.92 grams
4.92 grams of sodium phosphate (Na₃PO₄) are required to make 125 milliliters of a 0.240 M.