Chemistry Quiz CR1 and CR2

A positively charged particle found in the nucleus of an atom is called

• a neutron

• an electron

• a proton

• a quark

A negatively charged particle in an atom is the

• neutron

• proton

• electron

• quark

Where are electrons found?

• in the nucleus

• in the orbitals

• in the nucleus and in orbitals

• none of these

A change that creates a new substance and is usually not reversible is called

• a chemical property

• a physical property

• a chemical change

• a physical change

Two chemicals were mixed together. Bubbling occurred and a new color was observed. This is an example of

• a physical change

• a chemical change

• both a chemical and a physical change

• none of the above

If a substance is flammable, then to be safe you should

• wear gloves

• keep away from heat

• add heat

• see a symbol with a skull and crossbones

If a reaction absorbs heat it is called

• exothermic

• endothermic

• a nuclear reaction

• none of these

When handling poisonous materials you should

• not eat, drink or taste them

• wear goggles and gloves

• wash immediately with water if you contact them with your skin

• all of these

Which of the following is true?

• An atom has equal numbers of protons and electrons.

• The atomic mass gives you the number of electrons.

• The atomic number gives you the number of neutrons.

• An atom has a positive or a negative charge.

An atom becomes an ion when

• it gains or loses electrons

• it shares electrons.

• it is physically combined with other atoms.

• none of these