Yr9 Chemistry

An electron is

• positively charged

• neutral

• negatively charged

• cannot be determined

Conservation of mass means

• all the atoms present before a chemical reaction are not present after

• atoms present before chemical reactions are present after

• new substances and new elements are formed in a chemical reaction

• students should not add anything to the test tube during the experiment

A molecule is

• a singular particle of a particular element

• another name for an element

• 2 or more atoms that are combined

• a small piece of DNA

The type of reaction that releases energy as heat is called

• endothermic

• exothermic

• respiration

• photosynthesis

Tags

NGSS.HS-PS1-4

What is a charged atom known as?

• an ion

• an isotope

• an electron cloud

• a quark

The pH scale is a range from:

• 1-7
• 0-14
• 1-14
• 1-20

A(n) ______ is a substance with a pH less than 7

• Acid
• Alkaline
• Base
• Buffer

A(n) _______ is a substance with a pH greater than 7.

• Base
• Acid
• Buffer
• Water

What is the only substance with a neutral pH of 7?

• Milk
• Orange Juice
• Water
• Blood

Which solution releases H+ in solution?

• Base
• Acid
• Buffer
• Water