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  1. Problems
  2. /Atoms and Molecules
  3. /Laws of Chemical Combination

Laws of Chemical Combination

Chemistry
+ Upload a Problem
More in Atoms and MoleculesLaws of Chemical CombinationMolecules, Ions and FormulaeThe Mole ConceptMeasurement, Units and Significant FiguresStoichiometry and Concentration
14 problems
Type:
1.
At 110 °C and a fixed pressure, Meera sparks 50 mL of hydrogen with 20 mL of oxygen. New
High School (11–12) · Laws of Chemical Combination, The Mole ConceptStemPy LabStemPy Lab
Hard
2.
Sulfur forms two oxides. Oxide A is 50.0% sulfur by mass, and oxide B is 40.0% sulfur. New
High School (11–12) · Laws of Chemical Combination, The Mole ConceptStemPy LabStemPy Lab
Medium
3.
Two black powders are reduced to the metal. New
High School (11–12) · Laws of Chemical Combination, The Mole ConceptStemPy LabStemPy Lab
Medium
4.
Arun heats 24.5 g of potassium chlorate in a test tube. New
High School (11–12) · Laws of Chemical Combination, The Mole ConceptStemPy LabStemPy Lab
Easy
5.
An atom of hydrogen has a radius of about 0.1 nm.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Medium
6.
The atomic mass of sulphur is 32 u, and 1 u = 1.66 × 10⁻²⁴ g.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Easy
7.
Which idea of Dalton's atomic theory explains each of these?
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Easy
8.
A student sparks 9 g of hydrogen with 56 g of oxygen to make water.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Hard
9.
Nitrogen and hydrogen join in the ratio 14 : 3 by mass to make ammonia.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Medium
10.
Water has hydrogen and oxygen in the ratio 1 : 8 by mass.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Easy
11.
Three students heat substances in closed vessels and weigh them before and after.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Medium
12.
80 g of calcium carbonate is heated strongly.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Medium
13.
A student burns a candle on an open pan balance.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Easy
14.
36 g of magnesium burns completely in 24 g of oxygen.
High School (9–10), General · Laws of Chemical CombinationStemPy LabStemPy Lab
Easy