Question

Какая масса оксида кальция получится , если в реакцию с кальцием вступает кислород массой 6,4 г?

Answer 1

2Са + О2 = 2СаО 
кол-во о2=м/М=6,4г:32г/моль=0,2моль
по ур-ию реакции кол-во сао=0,4моль
м(сао)=количество*М=0,4моль*40+16г/моль=22,4г

Answer 2

Calculating the Mass of Calcium Oxide

To calculate the mass of calcium oxide produced when calcium reacts with oxygen, we can use the balanced chemical equation for the reaction between calcium and oxygen to form calcium oxide.

The balanced chemical equation for the reaction is: 2Ca + O2 → 2CaO

According to the stoichiometry of the balanced chemical equation, 2 moles of calcium react with 1 mole of oxygen to produce 2 moles of calcium oxide.

Given that the mass of oxygen is 6.4 g, we can calculate the mass of calcium oxide produced using the molar masses of the substances involved.

The molar masses are: - Calcium (Ca): 40.08 g/mol - Oxygen (O): 16.00 g/mol - Calcium Oxide (CaO): 56.08 g/mol

Using the molar masses and the stoichiometry of the balanced chemical equation, we can calculate the mass of calcium oxide produced.

Calculation

The molar ratio of oxygen to calcium oxide is 1:2. Therefore, the number of moles of oxygen is: moles of O2 = mass of O2 / molar mass of O2 moles of O2 = 6.4 g / 16.00 g/mol = 0.4 mol

According to the balanced chemical equation, the molar ratio of oxygen to calcium oxide is 1:2. Therefore, the number of moles of calcium oxide produced is: moles of CaO = 2 * moles of O2 moles of CaO = 2 * 0.4 mol = 0.8 mol

Finally, we can calculate the mass of calcium oxide produced using the number of moles and the molar mass of calcium oxide: mass of CaO = moles of CaO * molar mass of CaO mass of CaO = 0.8 mol * 56.08 g/mol = 44.864 g

Conclusion

Therefore, the mass of calcium oxide produced when 6.4 g of oxygen reacts with calcium is approximately 44.864 grams.