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WorksheetsChemical Formulas, Equations, and Reactions
Total questions: 13
Worksheet time: 7mins
Nitric acid has the chemical formula HNO3. How many atoms of nitrogen are in the formula?
0
1
3
5
A scientist analyzes a substance that is produced in a chemical reaction. The data show that each molecule of this product has three hydrogen atoms for every carbon atom. Which could be the formula for the substance?
CH4
C2H6
C3H8
C3H6
A model of a molecule is shown. Which substance could the model represent.
BH3
H2CO
H2O2
NaOH
Dolomite, CaMg(CO3)2, is a mineral used as an ingredient in concrete. How many carbon atoms are represented in the formula CaMg(CO3)2?
1
2
3
6
Which of these formulas does NOT contain the same number of nitrogen atoms as nitrous oxide, N2O?
NH4NO3
Cu(NO3)2
(NH4)2CO3
NaCN
Potassium bitartrate, also known as cream of tartar, is a white powder sometimes used in cooking. The formula for cream of tartar is shown below.
KC4H5O6
What is the total number of atoms shown in the formula?
(a)
The table shows the chemical formulas for four different compounds. In which compounds is the number of oxygen atoms four times the number of sulfur atoms?
Compounds 1 and 4 only
Compounds 3 and 4 only
Compounds 1, 3, and 4
Compounds 2, 3, and 4
Which of these activities with eggs involves a chemical change?
Frying a raw egg
Beating eggs and milk together
Drawing on the shell of a hard-boiled egg
Breaking a raw egg
Which of the following involves a physical change but no chemical change?
Nails rusting
Paper burning
Sugar dissolving
Leaves decaying
The photo shows a solid as it drops into water and starts producing bubbles. Which statement correctly explains the changes in the sold?
The solid is dissolving, so a chemical reaction is happening.
The formation of bubbles indicates that a chemical reaction is happening.
Since bubbles contain only gas, a chemical reaction is not happening.
Since no new solid is present, a chemical reaction is not happening.
A scientist carried out three experiments and recorded observations in a table. During each experiment, the scientist mixed together two substances. In which experiment(s) did a chemical reaction take place?
Experiment 1
Experiment 2
Experiment 3
Experiments 1, 2, and 3
A student used tongs to hold a strip of gray metal ribbon over a small flame. The burning metal ribbon produced a bright light. When the reaction ended, small pieces of white ash remained. The white ash would not burn. Which observation does NOT indicate that a chemical reactions took place?
The production of a bright light
The change from one piece of metal to many small pieces
The change from a gray metal to a white nonmetal
The change from a substance that burns to a substance that does not burn
Sodium chloride (NaCl) reacts with sulfuric acid (H2SO4). The products are sodium sulfate (Na2SO4) and hydrochloric acid (HCl). Four students wrote equations to represent this reaction. Which student wrote an equation that demonstrates the law of conservation of mass?
Student 1
Student 2
Student 3
Student 4
