What is evidence that a chemical change has happened?
O A. The temperature of a substance increases or decreases.
B. The amount of matter increases.
C. A substance changes into a new kind of substance.
O D. You observe a color change.

Answers

Answer 1
i think the answer is D

Related Questions

12.
Contrast and compare:
a) ionic and covalent bonding​

Answers

Answer:

Ionic bonds - an intramolecular force exist in a nonmetal and metal compounds such as NaCl. The Na donate 1 electon to Cl to complete its octet rule.

Covalent bond - an intramolecular force exist in a nonmetal and nonmetal compounds such as bonds O2, Cl2, CO2, sugar, proteins and most of organic compounds and biomolecules by sharing electrons to bond.

There are two types of covalent bonds: polar and nonpolar. Polar bond is a bond between two different nonmetal atoms of different electronegativities. While nonpolar bond is a bond between the same atom or two differenct atoms of the same electronegativities (if there is). Their electronegativities pull will cancel so that their overall polarity is zero.

At 303 K, the volume of a gas is 30.0 ml. At constant pressure, what is the new
volume of the gas if the temperature is decreased to 283K?

Answers

Answer:

V₂ = 28 mL

Explanation:

Given data:

Initial temperature = 303 K

Initial volume = 30.0 mL

Final temperature = 283 K

Final volume = ?

Solution:

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁  

V₂ = 30.0 mL × 283 K /303 K

V₂ = 8490 mL.K / 303 K

V₂ = 28 mL

Which models of the atom does the experimental evidence from Bohr's hydrogen experiment support? Explain why these models are compatible with the experimental results.

The models are Daltons, Thompsons, and Rutherfords

Answers

Answer:

Rutherfords

Explanation:

The model of the atom supported by Bohr's hydrogen experiment is the Rutherford's model of the atom.

Rutherford through his experiment on gold foil suggested the atomic model of the atom. The model posits that an atom has a small positively charged center(nucleus) where nearly all the mass is concentrated.

Surrounding the nucleus is the large space containing electrons. In the Bohr's model of the atom, he suggested that the extranuclear space of the atom is made up of electrons in specific spherical orbits around the nucleus.

Calculate the percent composition of C6H12O6

Answers

Answer:

Did you just let your cat walk on your keyboard? XD

Could you explain this a bit better please?

I'll answer the question in the replies of this comment if you can give me a bit more information.

Explanation:

May I have brainliest please? :)

How did the substance oxygen change the world??

Answers

Answer: The atmosphere of Earth wasn't always full of oxygen. ... An accidental mutation would some day change the world forever as these organisms would become able to feed off of the sunlight around them, and produce oxygen in a process known as photosynthesis. This oxygen, which none of these organisms could use, was toxic.

Plants make their own food and are not required to consume food for energy. Into which category does this characteristic cause plants to be assigned?​

Answers

Answer:

Autotrophic or Producers

Explanation:

They are often called producers because they make their own food.

Two individual atoms of the same element are slightly different. One has one more proton than it has electrons. The other has one more electron than it has protons. These atoms are both

ions
isotopes
freons
xenons
phlogistons

Answers

Answer:

ions

Explanation:

Individual atoms of the same element but having slightly different number of protons and electrons are called ions.

Ion is a charged particle.

An atom is made up of three fundamental subatomic particles. Protons are the positively charged particles Electrons are the negatively charged particles Neutrons do not carry any charges.

When the number of protons > electrons the body is positively charged.

When the number of electrons > protons the body is negatively charged.

Charged particles are called ions.

Below is a phase diagram for Carbon Dioxide. Use this diagram to answer the following question.
In this example we will start the Carbon Dioxide out at a temperature of -20oC and 1 atm of pressure. If the pressure was raised to 100 atm of pressure while still staying at -20oC, what phases would the Carbon Dioxide change between?

Answers

If you mark those points on the phase diagram it appears to be moving from vapor to liquid. If you can’t see how I determined that please let me know and I can further explain.

Vapor to liquid is the same as saying gas to liquid, which I believe to be the correct answer.

Help plz:))) I’ll mark u brainliest
ASAP!!!

Answers

Answer:

rank from lower to higher electronegativity

16)Li

   C

   N

17)Ne

  C

   O

18)Si

   P

   O

19)K

   Mg

   P

20)He

    S

    F

Heyyyyyyyy I’m smart I think I’m sorry

What are the coefficients that will balance the skeleton equation below?

___GaF3 +___KCN rightwards arrow___Ga(CN)3 + ___KF





A.
1, 3, 1, 3

B.
3, 1, 3, 1

C.
1, 1, 1, 3

D.
1, 3, 3, 1

1 points

QUESTION 6

The previous question is an example of what type of chemical equation?

A.
Synthesis

B.
Decomposition

C.
Single Re-Placement

D.
Double Re-Placement

Answers

1, 3, 1, 3

Explanation:

Ga - one on both sides

F - three on both sides

CN - three on both sides

K - three on both sides

But remember that CN was being multiplied by 3 on the right side already, meaning GA(CN)3 didn't mean a coefficient.

Answer:

Double re-placement

The two metals switched dance partners, that means it's a double.

Which of the following is true about waves?
A.
They are always visible.
B.
They always move matter.
C.
They carry energy.
D.
They can only travel though outer space.

Answers

Answer:

c. they carry energy is the answer

Answer:

C. they carry energy

Explanation:

Energy can be carried from one place to another by waves, including water, light, and sound waves. Waves are oscillating disturbances that travel through but do not move matter.

Infrared radiation escaping from hot coals is an example of invisible waves carrying energy. This energy can be felt as heat.

please help me..........​

Answers

Answer:

4/6

6/9

8/12

Explanation:

What is Jadi? is it goat? what language is Jadi?

Under a certain set of conditions, the percent yield of a reaction that produces carbon dioxide is 75.0%. What mass in grams of CO2 will actually be recovered if the theoretical yield is 26.7 grams?

Answers

Answer:

Actual yield = 20.03g

Explanation:

[tex]% yield = 100.\frac{actual yield}{theoretical yield}[/tex]% [tex]yield[/tex] = [tex]100. \frac{actual \ yield}{theoretical \ yield}[/tex]

Actual yield = % yield.(theoretical yield) / 100

Actual yield = 75.26.7/100

Actual yield = 20.025

Answer: I got 20.025 and then I rounded it to 20.0

Explanation:

What is the number of protons for the following?
190
+2
Os
76

Answers

Answer:

190+2=192

Explanation:

192 add it 192 added

Answer: they are right

Explanation:

This is due tomorrow so please help! : name a product where viscosity is important its creation or use explain why it is important

Answers

Like the other user stated, viscosity is an important property of fluid foods.it is defined and an internal friction of a liquid or it’s ability to resist flow

Relate pH values of 9.1, 1.2, and 5.7 to hydronium and hydroxyl ion concentration.

Answers

Answer:

9.1 = basic  1.2= very acidic  5.7= acidic

Explanation:

Question 4 of 10
What is the molarity of a solution of 3 moles (mol) of FeBr3 in 1/2 L water?
A.
3 mol/2L
B.
2L/3 mol
C.
0.5L/3 mol
D.
3 mol/0.5 L
SUBMIT

Answers

Answer:

B

Explanation:

Answer:

D. 3 mol/0.5 L

Explanation:

Just took the quiz

3.) All matter has both physical and chemical properties. A physical property is one that does not change the chemical nature of matter. Which of these choices is a physical property?
A.) height
B.) flammability
C.) ability to rust
D.) reaction with water

Answers

Answer:

D

Explanation:

It would be D because you are observing the reaction and don’t change anything

When the following equation is balanced, what is the coefficiant for Br?

___I2 +___NaBr rightwards arrow___NaI +_?_Br2

A.
6

B.
3

C.
1

D.
2

1 points

QUESTION 10

The previous question is an example of what type of chemical reaction?

A.
Synthesis

B.
Decomposition

C.
Single Re-Placement

D.
Double Re-Placement

Answers

Answer:

1. A 2. C

Explanation:

because it just is

How much heat is required to raise the temperature of a 6.21 g sample of iron from 25.0 oC to 79.8 oC?

Answers

Answer:

151.1J

Explanation:

Given parameters:

Mass of iron  = 6.21g

Initial temperature of iron  = 25°C

Final temperature of iron  = 79.8°C

Unknown:

Amount of heat = ?

Solution:

The amount of heat require to cause this temperature can be determined using the expression below;

    H  = m c (T₂ - T₁)

H is the amount of heat

m is the mass

c is the specific heat capacity

T is the temperature

    Specific heat capacity of iron 0.444J/g°C

Insert the parameters and solve;

     H  = 6.21 x 0.444 x (79.8 - 25)

     H   = 151.1J

Benzoic acid, C6H5COOH, is another derivative of benzene. The pH of an aqueous solution of benzoic acid at 298 K is 2.95. Determine the concentration of hydroxide ions in the solution,

Answers

Answer:

[OH⁻] = 8.91x10⁻¹²M

Explanation:

In aqueous solutions, the [OH] and [H⁺] are associated in the equation of hydrolisis of water:

1x10⁻¹⁴ = [OH⁻] [H⁺]

With pH, we can solve for [H⁺] and obtain, the [OH⁻] using this equation:

pH = -log [H⁺]

[H⁺]= 10^-pH

[H⁺] = 1.122x10⁻³M

1x10⁻¹⁴ = [OH⁻] [1.122x10⁻³M]

[OH⁻] = 8.91x10⁻¹²M

BRAINLEST WILL BE GIVEN TO A RIGHT ANSWER!!!!

Potassium (K) has a charge of +1, and sulfur has a charge of –2. Which best describes the compound they make?

A) The chemical formula is K2S, and the name is potassium sulfide.

B) The chemical formula is KS2, and the name is potassium sulfide.

C) The chemical formula is K2S, and the name is sulfur potassium.

D) The chemical formula is KS2, and the name is sulfur potassium.

Answers

Answer:

A) The chemical formula is K2S, and the name is potassium sulfide. Explanation:

edge

What is a non-example of a nucleus? Please give me a non-living thing.

Answers

Answer:

They are prokaryotes and both have tough cell walls. ◦ The cytoplasm contains ribosomes, but no organelles. ◦ There is no nucleus for organisms in this category.

Explanation:

Answer:

rock- non living

( Prokaryotes don't have a nucleus)

Explanation:

In your own words, please explain how to name acids.

Answers

Answer:

Acids are named based on their anion — the ion attached to the hydrogen. In simple binary acids, one ion is attached to hydrogen. Names for such acids consist of the prefix “hydro-“, the first syllable of the anion, and the suffix “-ic”. Complex acid compounds have oxygen in them.

A metal atom and a non-metal atom bond together. What type of bond do they form?

Question 8 options:

Ionic


Round


Covalent


Glue

Answers

Answer: Iconic

Explanation:Ionic bonds are formed through the exchange of valence electrons between atoms, typically a metal and a nonmetal.

A wave is a _____that transfers _____ through a ______
A.) medium, disturbance, energy
B.) disturbance, energy, medium
C.) energy, disturbance, medium
D.)disturbance, medium, energy

Answers

The correct answer is B.) disturbance,energy,medium

A wave is a  disturbance that transfers energy through a medium. There

are types of  such as sound and light waves.

A wave involves the transfer of energy such as sound, light waves etc

through a medium. The medium could be through liquids , solids or air and

they have characteristic waves which pass through them.

When a wave transfers energy through a medium, the matter involved

doesn't experience any type of movement.

Read more on https://brainly.com/question/19210453

SOMEONE HELP ME PLEASE ILL GIVE BRAINLY!

Is the following picture an example of a chemical change or a physical change?

A chemical change, because the atoms are rearranging to form new molecules.

A physical change, because the molecules are staying the same.

A chemical change, because the molecules are staying the same.

A physical change, because the atoms are rearranging to form new molecules.

Answers

Answer:

It would be a physical change, because the atoms are rerranging to form new molecules!

Explanation:

Why should a hypothesis be testable?
A. It must be testable in order to be found true or false.
B. It must be testable for the outcome to be predictable.
C. It must be testable for other scientists to consider it reliable.
D. It must be testable if it is to become a scientific theory.

Answers

A. It must be testable in order to be found true or false.

A bus travels a distance 150km
in 5 hours where as another bus travel 200km in
6 hours which bus travel fast

Answers

Answer: The bus traveling 200km in 6 hours is traveling the fastest.

Explanation:

Bus 1

150km/5hrs

Simplify -> 30km/hr

Bus 2

200km/6hrs

Simplify -> About 33.333km/hr

Question 14
1 pts
How many moles of NaCl could be found in 0.4 L of a 0.9 M solution? Round your answer to
two decimal places.

Answers

Answer:

0.36mol

Explanation:

Given parameters:

Volume of NaCl  = 0.4L

Molarity  = 0.9M

Unknown:

Number of moles  = ?

Solution:

To find the number of moles, the molarity of a solution is the amount of solute contained in a solution.

 Molarity  = [tex]\frac{number of moles}{volume}[/tex]  

 Number of moles = molarity x volume

 Insert the parameters and solve;

 Number of moles = 0.4 x 0.9  = 0.36mol

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