# A change of state requires the addition or removal of heat energy. True False

Yes, this is true. Let’s take water for example, it has 3 states: solid, liquid, and gas. If you want to turn water into a gas (into water vapor) you need to boil it, which is applying heat. Similarly, you need to freeze it (remove heat) to turn into a solid state.

## Related Questions

The most common form of matter in the universe is _____.

plasma
gas
liquid
solid

Plasma would be the most common form of matter in the universe.

Explanation:

For conduction to occur, particles must be . Word Bank: in contactnear each otherroundbig

in contact

Explanation:

conduction requires direct contact with whatever form of heat.

in contact

Explanation:

conduction can only occur when the particles are in contact with each other.

8. 71.67 g of InBr2 was dissolved in water to a final volume of 650 mL. (A) What is the molar concentration of indium in the resulting solution? (B) If 25.0 mL of the solution in part A was diluted to 75.0 mL, what is the molar concentration of the resulting solution?

A) 0.39 M is the molar solution of the resulting solution.

B) The resulting solution will have molarity  of 0.13M

Explanation:

The atomic weight of 2 atoms of bromine = 79.904 gms

The atomic weight of 1 atom of In = 114.818

Atomic weight of InBr2 = 274.26 gm

From the data mass percentage is calculated ie. 58.19% of bromine, 41.80 % of Indium

so from the mass of the InBr2 the percentage of indium can be calculated as

41.088/100* 71.67

= 29.447 grams

No of moles of indium= 29.04/114.818

= 0.256 moles

In the solution of 650 ml 0.256 moles of Indium are there

M=n/C

= 0.256/650ml

=  0.256/0.65 litre

= 0.39 M

B) in 25 ml of the solution the molarity is 0.39 which is diluted to 75 ml ie three fold diluted the molarity decreases .

from the formula M1V1=M2V2

= 0.39*25= M2 *75

M2= O.39*25/75

= 0.13 M

18 POINTSSSSSSSSSSSSSSSSSSS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Asexual reproduction?

Definition: Asexual reproduction is a type of reproduction which does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from a single cell or from a multicellular organism inherit the genes of that parent.

Types:

Budding- A form of asexual reproduction of yeast in which a new cell grows out of the body of a parent.

Vegetative Reproduction- Plants budding which creates a runner hich sends a clone
Strawberries plants
Dandelion

Parthenogenesis- An unfertilized egg develops into an adult (Aphids, honeybees, lizards)

Binary Fission- One cell splits into two cells
Allows for no genetic variety
Bacteria performs it
Protests perform it but takes longer

Regeneration- The ability to regrow a missing part of the body by Mitosis

Fragmentation- A small piece of an organism breaks away from it and develops into a new individual (star fish)

Spores- Contain DNA, cytoplasm, and tough putter wall protects it from dying out produced by many organisms (algae, fungi, bacteria)

Advantages: Allows rapid populating, does not need mates, does not require mobility, friendly to the environment, handy in case of emergency.

Disadvantage: poses some inheritance issues, can lead organism to being prude to extinction, carries problems with population control, causes organism to not be able to adapt and results in poor conditions to subject

Asexual reproduction is a type of reproduction which does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from a single cell or from a multicellular organism inherit the genes of that parent.

Explanation:

How do you calculate the theoretical yield and percentage yield of a chemical equation?

Theoretical yield is the result obtained from your calculations.

Percentage yield is the ratio of the actual yield ( i.e yield obtained from your experiment) to theoretical yield x 100 i.e

%yield = Actual yield / Theoretical yield x 100

Yo sup??

The theoretical yield will be given in the question.

To calculate the percentage yield use the formula

percentage yield=(observed yield/theoretical yield)*100

Hope this helps

Give reason :- Steam produce severe burns than boiling water.

Steam produces more severe burns than boiling water because the LATENT HEAT of steam is greater than water. It means that steam has greater heat energy than boiling water which causes more severe burns.

What is suspension in chemistry​

it's the example of heterogeneous mixture..

What is the hydrogen ion concentration of a solution with pH = 8.75 ?

Explanation:

Using the formula

pH = -log[H^+]

Since the pH of the solution has been given to be 8.75,

Therefore,

8.75= -log [H^+]

Let's take H^+ to be x

8.75= -log x

Let's look for x, since the log is in base 10

X = 10^-8.75

X = 1.778 * 10^ -9

Therefore, H^+ =1.778 *10^-9

Of 0.605 g of magnesium hydroxide reacts with 0.800 g of sulfuric acid, what is the mass of magnesium sulfate produced? Steps would be appreciated! Thanks (:

Mass = 0.963 g

Explanation:

Given data:

Mass of Mg(OH)₂ = 0.605 g

Mass of H₂SO₄ = 0.800 g

Mass of MgSO₄ = ?

Solution:

Chemical equation:

Mg(OH)₂  +  H₂SO₄   →    MgSO₄ + 2H₂O

First of all we will calculate the number of moles of each reactant.

Number of moles of Mg(OH)₂:

Number of moles = mass / molar mass

Number of moles = 0.605 g / 58.32 g/mol

Number of moles = 0.01 mol

Number of moles of H₂SO₄ :

Number of moles = mass / molar mass

Number of moles = 0.800g / 98.08 g/mol

Number of moles = 0.008 mol

Now we will compare the moles of MgSO₄ with  Mg(OH)₂ and  H₂SO₄

Mg(OH)₂         :           MgSO₄

1                 :               1

0.01            :            0.01

H₂SO₄             :           MgSO₄

1                      :               1

0.008                :            0.008

The number of moles of magnesium sulfate produced by sulfuric acid are less so it will be a limiting reactant.

Mass of magnesium sulfate:

Mass = number of moles × molar mass

Mass = 0.008 mol × 120.37 g/mol

Mass = 0.963 g

Question 4 of 15 2 Points
If 100 joules of heat are added to a gas in an isochoric process, what is the
change in its internal energy?
O A. -100
O B. 300 j
.2003
O D. 100

Explanation:

100 J

Explanation:

I've just answered this on a quiz

For a different reaction, Kc = 1.39, kf=12.6s−1 , and kr= 9.08 s−1 . Adding a catalyst increases the forward rate constant to 4.28×103 s−1 . What is the new value of the reverse reaction constant, kr, after adding catalyst?

Explanation:

The equilibrium constant is equal to the quotient of the forward rate to the reverse rate.

Adding a catalyst increases both the forward rate and the reverse rate in the same proportion without net effect on the equilibrium position.

Then, the equilibrium constant before and after adding the catalyst is the same.

Thus, knowing the forward rate constant and the equilibrium constant you can determine the reverse rate constant:

1. Which is not an example of a physical change to a wooden stick? A) slicing wood shavings from the stick
B) bending the stick back and forth
C) burning the stick
D) chopping the stick in half

The answer is C. burning the stick. This is because burning the stick will change the chemical properties of the wood, and it will not be wood anymore, it will be ash and the rest will be heart or gas.

C) Buring the stick

Explanation:

Oh no! The thermometer punctured a hole in the bottom of the coffee cup, and water is spilling out.
Check all actions you would take.
Throw the broken pieces away.
Use the punctured cup as the outside cup,
not the inside cup.
0 Replace the cup
O Clean the area
| Mention the spill to the teacher.
O Call 9-1-1

Answer:Throw the broken pieces away, Replace the cup, Clean the area, Mention the spill to the teacher.

Explanation:

1,3,4,5

Explanation:

A chemistry teacher adds 50.0 mL of 1.50 M H2SO4 solution to 200 mL of water. What is the concentration of the final solution? Use M subscript i V subscript i equals M subscript f V subscript f..
0.300 M
0.375 M
6.00 M
7.50 M

Explanation:

This question tests for concentration after dilution of the solution. is added to 200ml of water.

The formula for concentration correlation is given as , where the latter relates to the final solution mix.

Therefore the concentration is 0.300M

a on edge

Explanation:

Lab Report: Factors Affecting Solution Formation 1. On the basis of your results, what is the relationship between the temperature of the solvent and the solubility of KCl and KClO3 (Show the both graphs)?

2. Provide the two unknowns A and B and describe how you determined the identity using your data.

3. Explain three factors the affect how fast substances dissolve.

Maybe the number of atoms, Numbers of ions formed, and strength of the various bonds.

Explanation:

Bicycles- How do different forms of transportation meet people’s transportation needs?

Answer: Different ways of transportation mean getting to one place by multiple different transportation it actually all  depends on were you need to go

Explanation:

Some forms of transportation are meant for small rides or trips while other forms are meant for long far away rides

Which example of transportation most likely involves the widest variety of vehicles? A. Blood is rushed from a blood bank to a local hospital.
B. Fresh vegetables are transported from a farm to a nearby city.
C. science textbook is transported from a printer in China to your school, and then to your home.
D. Gravel from a gravel pit is transported to construction sites across the state.

C. Science textbook is transported from a printer in China to your school, and then to your home.

In the equation below, identify the Brønsted-Lowry acid, Brønsted-Lowry base, conjugate acid, conjugate base. NH4+(aq) + NO-2 (aq) = HNO2(aq) +NH3(aq)

HNO₂ is Bronsted- Lowery conjugate acid.

NH₃ is Bronsted- Lowery conjugate base.

NH₄⁺(aq)  is  Bronsted- Lowery acid.

NO₂⁻²is  Bronsted- Lowery base.

Explanation:

Bronsted- Lowery acid:

Bronsted- lowery acid is the specie which have capability to donate the proton.

Bronsted- Lowery conjugate base:

The Bronsted- Lowery conjugate base of Bronsted- Lowery acid is the specie which is formed after when an acid donate the proton.

Bronsted- Lowery base:

Bronsted- lowery base is the specie which have capability to accept the proton.

Bronsted- Lowery conjugate acid:

The Bronsted- Lowery conjugate acid of Bronsted- Lowery base is the specie which is formed after when an base accept the proton.

Chemical equation:

NH₄⁺(aq) + NO₂⁻²(aq) → HNO₂(aq) + NH₃(aq)

NH₄⁺(aq)  have an extra proton and can donate it so it is Bronsted- Lowery acid.

NO₂⁻² have negative charge and can accept the proton so it is  Bronsted- Lowery base.

HNO₂ is Bronsted- Lowery conjugate acid.

NH₃ is Bronsted- Lowery conjugate base.

Which of these factors make hydrogen fuel cells a better option than burning fossil fuels

Explanation: Fossil fuels mess up the air while Hydrogen fuel cells keep the air clean

1 Point What is the temperature in kelvins of 23°C?
O A. 11.9K
O B. 6279K
OC. 296K
O D. 250k

Option C. 296K

Explanation:

T°C = 23°C

To covert the above to Kelvin temperature, use the following equation

T(K) = T°C + 273

T(K) = 23 + 273

T(K) = 296K

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