Chemical Reactions

Water is a neutral substance, what is its pH?

• 4

• 6

• 7

• 9

According to the theory of conservation of mass, which property of the reactants is always unchanged after a chemical reaction?

• mass

• colour

• state

• volume

The chemical found in chloroplasts that traps light in photosynthesis in plants is called _______________

• chloroform

• chlorophyll

• chloroplast

• chloride

In your own words, what is a chemical reaction?

• A process where substances are transformed into different substances

• A physical change in the state of matter

• A method of separating mixtures

• A technique for measuring temperature

What is the balanced chemical equation for the reaction: N₂ + H₂ → NH₃?

• N₂ + 3H₂ → 2NH₃

• N₂ + H₂ → NH₃

• 2N₂ + 3H₂ → 2NH₃

• N₂ + 2H₂ → NH₃

The pH range of an acid is:

• 0 to 7

• 7 to 14

• 14 to 21

• -7 to 0

To make something more acidic, should you add more OH- or H⁺ ions?

• Add more OH-

• Add more H⁺ ions

Bases are also used in everyday life and are mostly found in different cleaning products. What are two characteristics of a base?

• Sour taste and turns red litmus blue

• Bitter taste and slippery feel

• Sweet taste and turns blue litmus red

• Neutral taste and no effect on litmus

What is the pH range of a base?

• 0-7

• 7-14

• 14-21

• Neutral

Inside of an atom we can find three different things, what are the charges for the following: Electrons - ________________________ Protons - ________________________ Neutrons - ________________________

• Electrons - Negative, Protons - Positive, Neutrons - Neutral

• Electrons - Positive, Protons - Negative, Neutrons - Neutral

• Electrons - Neutral, Protons - Positive, Neutrons - Negative

• Electrons - Negative, Protons - Neutral, Neutrons - Positive