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A 2.026g sample of a hydrate of sodium carbonate (Na2CO3) is heated to remove water. After heating, the mass of the sample is 0.750 g. Calculate the percentage by mass of water in the sample.

2 Answers

5 votes

Answer:

percentage mass of water = 62.98%

Step-by-step explanation:

The reaction is a decomposition reaction whereby hydrate of sodium carbonate was heated to remove water . The actual weight of the hydrated compound is 2.026 grams . After heating, the mass of the sample was now 0.750 grams. The percentage of the water sample can be calculated as follows:

total mass of hydrated sample = 2.026 grams

mass of sample after heating = 0.750 grams

mass of water removed = 2.026 - 0.750 = 1.276 grams

percentage mass of water = mass of water/mass of hydrated compound × 100

percentage mass of water = 1.276/2.026 × 100

percentage mass of water = 127.6/2.026

percentage mass of water = 62.9812

percentage mass of water = 62.98%

User Verunar
by
5.7k points
4 votes

Answer:

62.98 % of the sample of hydrate is water

Step-by-step explanation:

Step 1: Data given

Mass of the sample of a hydrate of sodium carbonate (Na2CO3) = 2.026 grams

After heating, the mass of the sample is 0.750 g

Molar mass H2O = 18.02 g/mol

Step 2: Calculate mass of water

Mass water = mass of hydrate - mass of sample after heating

Mass water = 2.026 grams - 0.750 grams

Mass water = 1.276 grams

Step 3: Calculate mass % percent of water

Mass % of water = (mass of water / total mass hydrate) * 100 %

Mass % of water = (1.276 grams / 2.026 grams) *100 %

Mass % of water = 62.98 %

62.98 % of the sample of hydrate is water

User Josh Hinman
by
5.6k points