8th Grade Chemical Change Quiz

1.

5 points

When an object has more electrons than protons it is positive.

True

False

2.

5 points

What is the charge of an atom that has lost an electron?

Negative

Neutral

Positive

3.

5 points

The law of conservation of matter applies to physical and chemical change.

True

False

4.

5 points

What part of the atom is involved in a chemical change?

protons

electrons

neutrons

5.

5 points

What part of the atom is involved in a chemical change?

neutrons

protons

electrons

6.

5 points

Bonding by transfer is when an atom.....

shares an electron

loses or gains electrons

does not obey the law of conservation of matter

occurs only in water molecules

all of the above

7.

5 points

All chemical changes produce new substances with new and different properties.

True

False

8.

5 points

All atoms within the molecules that form the reactants appear again in the products but rearranged into different molecules or compounds.

True

False

9.

5 points

Opposite charges attract

True

False

10.

5 points

The law of conservation of matter is:

the idea that equations must be balanced.

the idea that matter can not be created or destroyed

thought to be only a theory

all of the above

none of the above

A and B only

B and C only

11.

5 points

Bonding by transfer is also known as ionic bonding.

True

False

12.

5 points

What is the charge of an atom that has gained an electron?

Negative

Neutral

Positive

13.

5 points

The following equation is not balanced, what would make it balanced?

H2 + O ---------------> 2 (H2O)

add a 2 in front of the H2 and a 2 in front of the O.

adda 4 in front of the H and leave the o alone.

nothing it is balanced already.

14.

5 points

Bonding by sharing is also known as covalent or molecular bonding.

True

False

15.

5 points

How many electrons does oxygen want in it's outer shell?

5

8

6

2

16.

5 points

The number of atoms in the reactants must equal the number of atoms in the products.

True

False

17.

5 points

Evidence that a chemical change has taken place includes:

odor released

precipitate forms

color change

all of the above

none of the above

18.

5 points

Bonding by sharing is when an atom gains electrons and bonds with an atom that has an opposite charge.

True

False

19.

5 points

A cation is a negatively charged particle.

True

False

20.

5 points

An ion is a charged atom.

True

False

21.

5 points

An example of a chemical change in matter is:

water boiling

ice melting

paper burning

deposition

22.

5 points

When salt is added to water and the freezing temperature is reduced this is a chemical change.

True

False

23.

5 points

Valence electrons are outer shell electrons involved in chemical bonding.

True

False

24.

5 points

What rule states that the outer shell electrons can only hold eight electrons?

the octet rule

the law of conservation of matter

the law of inertia

valence electrons rule

25.

5 points

Three chemical properties include mixing with an acid, mixing with electricity, and mixing with___________________.

glue

atoms

sublimation

oxygen

26.

5 points

Why is it important to balance equations?

to show the law of conservation of matter

to show that matter can not be created or destroyed

The total number of atoms in the reactants must equal the number of atoms in the products

all of the above

27.

5 points

A new element is formed in a chemical change.

True

False

28.

5 points

A balanced equation shows that matter is conserved in a chemical reaction.

True

False

29.

5 points

What happens to bonds or links between atoms to produce a new product?

they slip and slide past each other

they break

they vibrate in place

they move in a random pattern

30.

5 points

Oxygen has an atomic number of 8.

How many electrons are there in the outer shell of oxygen?

5

2

6

8