Which of the following does not happen during a chemical change?

Mass is gained.

New compounds are formed.

Old compounds are broken down.

Bonds are broken.

Calcium oxide (CaO) can react with carbon dioxide (CO2) in a synthesis reaction. Select the most likely products of this reaction. CaO + CO2 →?

The following reactions all occur in a blast furnace. Which of these are redox reactions? (a) 3Fe2 O3 (s) + CO (g) ⟶ 2Fe3 O4 (s) + CO2 (g) b) Fe3 O4 (s) + CO (g) ⟶ 3FeO (s) + CO2 (g) c) FeO (s) + CO (g) ⟶ Fe (l) + CO2 (g) d) C (s) + O2 (g) ⟶ CO2 (g)

I really like this guy and he is showing signs like as if he likes me but i still think he likes me as a friend. What do i do? Do i tell him i like him or not because it might ruin our friendship?

Cindy predicts that plastic foam insulates cold drinks better than metal or ceramic materials do. To test the hypothesis, she fills cups made from these materials with equal amounts of cold water.

a sample of gas under 3K Pa pressure has a volume of 13 L at 56.12 Kelvin. if the pressure is increased to 70 kPa the volume would decrease to 7 liters what would be the new temperature

Which statements are true? na + is formed from the reduction of na (s). the oxidation number for hg (?) is 0. the oxidation number for cu (s) is + 2. zn2 + is formed from the oxidation of zn (s). a reducing agent gains electrons.

An apple pudding is prepared by combining apples, sugar, butter, and lemon juice. To which category does it belong? A) Compound B) Mixture

How many electrons does carbon need to gain to obtain a noble gas electron configuration

What is the pH of a solution of 0.750 M KH2PO4, potassium dihydrogen phosphate?

What science was developed later which was found to support darwins theory