3. Chemical Reactions

Empirical Formula

Multiple Choice
Determine the empirical formula for a compound that is 36.86% N and 63.14% O by mass.
Multiple Choice
A compound is found to be 30.45% nitrogen (N) and 69.55% oxygen (O) by mass. If 1.63 g of this compound occupy 389 mL at 0.00°C and 775 mm Hg, what is the empirical formula of the compound?
Multiple Choice
Which of the following could be both a molecular formula and an empirical formula?
Multiple Choice
Covalent compounds
Multiple Choice
In order to make 1 s’ more, you need 2 graham crackers, 1 piece of chocolate, and 1 marshmallow. How many s’mores can be made from the following ingredients?
7 graham crackers, 6 pieces of chocolate, and 5 marshmallows
Multiple Choice
A chemist wishing to identify a compound determines the masses of its elements as: 1.445 g S and 6.391 g Cl. Determine its empirical formula.
Multiple Choice
Determine the simplest form of a compound made up of carbon, hydrogen, nitrogen and oxygen if it is made of 49.48% C, 5.19% H and 16.48% O.
Multiple Choice
A compound composed of potassium, manganese and oxygen contains 3.12 g potassium and 1.922 x 10²³ oxygen atoms. If a sample of the compound weighs 12.61 g determine its empirical formula?
Open Question
What is the empirical formula of a compound that contains only iron and oxygen and is 22.27% oxygen?
Open Question
In general, what does a subscript (such as the "2" in H₂) tell you about the molecule?
Open Question
How many atoms of oxygen are in the chemical formula 2Ca(ClO₂)₂?
Open Question
Some of the formulas below could be either molecular or empirical formulas; however, some could only be molecular formulas. Which of the following formulas must be molecular formulas? Select all that apply.
Open Question
Which of the following is an empirical formula?
Open Question
A 4.08 g sample of a compound of nitrogen and oxygen contains 3.01 g of oxygen. What is the empirical formula?
Open Question
What is the empirical formula of a compound that contains 75% Ag and 25% Cl by mass?