Chem Test 3

An empirical formula:

• is a formula that calculates the coefficients of a compound in a balanced equation.
• is the simplest whole-number ratio of moles of elements in the compound.

You are given the following percentages: 40.05% S and 59.95% O. Find the empirical formula for these elements. (keep two decimal places throughout calculations)

• SO
• SO₂
• SO₃
• SO₄

What is the empirical formula if you have 88.80% copper and 11.20% oxygen?

• Cu₃O₈
• CuO₄
• Cu₂O
• Cu₄O₁₀

In a chemical equation, is it true that -

• the reactant side and product side can have different numbers of atoms for each element
• there can be different elements on the reactant side and the product side
• an element or compound must be accompanied by a phase change
• the coefficients indicate the number of molecules of each reactant used and the number of molecules of each product made

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In a chemical equation, is it true that -

• the reactant side and product side can have different numbers of atoms for each element
• there can be different elements on the reactant side and the product side
• an element or compound must be accompanied by a phase change
• the coefficients indicate the number of molecules of each reactant used and the number of molecules of each product made

The formula below represents the most common carbohydrate known as glucose. Which information can be determined from the chemical formula?
C₆H₁₂O₆

• The structural arrangement of the atoms in a glucose molecule
• The color of a glucose molecule
• The size of a glucose molecule
• The number of atoms of each element in a glucose molecule

Tags

NGSS.MS-PS1-1

What is a double replacement?

• Two compounds react to form two new compounds.
• One compound reacts to form two separate elements.
• Two elements reacting to form a single compound.
• A hydrocarbon and 

What is a precipitate?

• A solid formed from a single replacement reaction
• An aqueous compound formed from single replacement reaction 
• An aqueous compound formed from double replacement reaction
• A solid formed from a double replacement reaction

What is the generic equation for a double replacement reaction? 

• AB + CD ---> AD + CB
• AB + CD ---> DA + CB
• AB + CD ---> A + BC
• AB + CD ---> D + CBA

What is the generic formula for a single replacement reaction? 

• A + BC ---> CA + B
• A + BC ---> BC + A
• A + BC ---> AB + C
• A + BC ---> AC + B