Chemistry unit 2 review

Which of the following is a compound?

• O2

• H2O

• Na

• H+

Tags

NGSS.MS-PS1-1

This subatomic particle has a charge of +1

• Proton

• Neutron

• Electron

This subatomic particle has a charge of 0.

• Protons

• Neutrons

• Electrons

Which of the following subatomic particles determines the atomic mass number

• Protons

• Neutrons

• Electrons

How many protons are present in this atom of iron?

• 26

• 55

• 56

• 30

Tags

NGSS.MS-PS1-1

The mass of an object is 30 g.  The volume is 5 mL.  What is the density of this object?

• 3 g/cm

• 6 g/mL
• 8 g

A bar of copper has a mass of 216g and a volume of 24cm³. What is the density of copper?  

• 9g/cm3
• .11g/cm3
• 5184g/cm3
• 322mL

As part of a classifying elements lab Joe was finding the density of different samples. One sample had a mass of 26.4 and a volume of 12 mL. What element is it?

• Sulfur

• Carbon

• Boron

• Krypton

What is Half-life?

• The amount of time it takes for some of the nuclei in a sample of the isotope to decay
• The amount of time it takes for half the electrons in a sample of the isotope to decay
• The amount of time it takes for half the nuclei in a sample of the isotope to decay
• the amount of time it takes to double the nuclei in a sample of the isotope to decay

Tags

NGSS.HS-PS1-8

What is the half-life of iodine-131?

• 32 days
• 8 days
• 16 days
• 24 days

Tags

NGSS.HS-PS1-8