7.6B, 8.6B & 8.6E Quizizz Questions

What do scientists use to identify the elements present in a molecule?

• chemical symbol
• subscript
• elements in Group 18
• chemical formula

When do we use parentheses in a chemical formula?

• any time there is a subscript
• only when we have a coefficient
• when there is a special subgroup of atoms
• whenever there is an invisible “1”

What does a subscript tell us?

• how many atoms of each element are in a molecule
• the charge of the ion
• the amount of molecules in a reaction
• the atomic number of the element

What are chemical formulas made up of?

• electrons and coefficients
• chemical symbols and subscripts
• molecules and elements
• atoms and electrons

If there is no number after a chemical symbol, how many atoms of that element are there?

• 0
• 1
• 2
• We do not know how many.

When are parentheses needed in a chemical formula?

• never
• always
• to group certain atoms together
• when there is an invisible “1”

What inspired Dmitri Mendeleev to create the periodic table?

• He wanted to win a scientific competition.
• He noticed patterns and connections among elements.
• He was trying to create a new type of element.
• He was following the instructions of his professor.

Elements in the same group have what in common?

• chemical properties
• physical properties
• atomic mass
• atomic number

What are the horizontal rows in the periodic table called?

• groups
• columns
• periods
• families

Which reaction involves elements from Group 2 and Group 16?

• H2​ +Cl2​ → 2 HCl
• Na+Cl2 ​→ 2 NaCl
• 4 Fe+3O2​ → 2 Fe2​O3​
• 2 Ca+O2​ → 2 CaO