Chemistry 2nd Nine Weeks Practice Test

Elements in the same column of the periodic table always have the same # of _______ as one another.

• Protons
• Neutrons
• Electrons
• Valence Electrons

Tags

NGSS.HS-PS1-1

Which group has the greatest number of valence electrons?

• 1
• 14
• 18
• 16

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which elements have the most similar chemical properties?

• boron and carbon

• oxygen and sulfur

• aluminum and bromine

• argon and silicon

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.
What is the average mass of this element?

• 74.92 amu
• 24.97 amu
• 75.01 amu
• 74.51 amu

Calculate the average atomic mass of silver.

• 106.38649amu
• 111.91896amu
• 107.8677amu
• 121

Tags

NGSS.HS-PS1-7

What was Dmitri Mendeleev's greatest contribution to the history of the periodic table?

• He arranged all of the known elements by their atomic number
• He realised that there was a pattern of reactivity which repeated every 8 elements
• He predicted the existence (and properties) of new elements
• He identified the "law of triads" which became the groups

Why were there blank spaces left in Mendeleev's periodic table?                                              

• He didn't know what to put there.
•  Undiscovered elements not yet known.
• Multiple elements could have fit
• He forgot to add the elements in.

Moseley discovered that the ________ was the most fundamental property needed for organization.                                                 

• atomic mass

• mass number

• atomic number

• number of protons

Which group of elements have the most reactive nonmetals?

• metalloids
• halogens
• alkali metals
• noble gases

Which group of elements have the most stable, nonreactive elements (will not bond with others)?

• metalloids
• halogens
• alkali metals
• noble gases