Staar Chemistry

Which of the following properties uniquely identifies every element?

• Number of valence electrons
• Phase at room temperature
• Number of protons
• Charge of the atom

An elements reactivity and other chemical properties are determined by the number of….

• isotopes it has.
• oxidation states
• orbitals in an atom.
• valence electrons

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Molybdenum has an atomic number of 42. This means that  molybdenum...

• has a freezing point of 42 degrees Fahrenheit.
• belongs to Group 42 on the Periodic Table.
• Can form 42 bonds with other atoms.
• contains 42 protons in its nucleus.

Which of the following properties of carbon distinguishes it from all other elements?

• Carbon has 6 protons in its nucleus.
• Carbon is a gray solid at room temperature.
• Carbon forms compounds with oxygen.
• Carbon can be found in Earth's crust.

Based on this table it can be concluded that

• Sodium is the most reactive
• strontium is the best conductor
• phosphorous is the least stable
• aluminum has the most protons

Tags

NGSS.HS-PS1-1

Which pair of elements have the same number of valence electrons?

• Lithium and Beryllium
• Magnesium and Sodium
• Lithium and Sodium
• Magnesium and Lithium

Tags

NGSS.HS-PS1-1

What do elements in group 1 have in common?

• Number of valence electrons 
• Melting point of the element
• Possible number of bonds formed
• Metallic characteristics of the element

Tags

NGSS.HS-PS1-1

Which element would have similar properties to Sulfur?

• Nitrogen
• Oxygen
• Flourine
• Chlorine

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which of the following statements is true….

• A period is another name for a row
• Elements in the same period share similar physical properties
• Elements in the same period have the same number of energy shells surrounding the nucleus
• All of the above

Tags

NGSS.HS-PS1-1

I which location on the Periodic Table are nonmetals found?

• Location 1
• Location 2
• Location 3
• Location 4

Tags

NGSS.HS-PS1-1