What is the same within each group on the periodic table?

• the number of protons
• the number of electrons
• the number of atoms
• the number of valence electrons

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

A combination of substances that are not chemically combined is called a(n)____________. 

• mixture
• compound
• physical

This picture represents which of the following?

• element
• compound
• mixture

Tags

NGSS.MS-PS1-1

Which solution releases H+ in solution?

• Base
• Acid
• Buffer
• Water

A solution with a pH of 3.6 would be...

• Acid
• Base
• Neutral
• Acid and Base

A solution with a pH of 9.5 would be...

• Acid
• Base
• Neutral
• Acid and Base

A solution with a pH of 7.0 would have...

• more H ions than OH ions
• more OH ions than H ions
• equal number of H and OH ions
• None of these.

In the equation,          2Mg + O₂ ---> 2MgO, which are the reactants?

• Mg and O
• MgO
• Mg and MgO
• O and MgO

Tags

NGSS.MS-PS1-2

Which equation obeys the law of conservation of mass?

• H₂ + O₂ ------>  H₂0
• C + 2H₂ ---->  CH₄
• 2Fe₂O₃  ------> 2O₂ + 4Fe

Tags

NGSS.MS-PS1-5

Name ALL the evidences that show a chemical reaction has occurred.

• color, gas, light
• light, precipitate, odor, 
• color, gas, light, temperature, precipitate
• temperature, smell, light, conductivity, taste

Tags

NGSS.MS-PS1-2