Answer:
34.15% is the mass percentage of calcium in the limestone.
Explanation:
Mass of precipitate that is calcium oxalate = 140.2 mg = 0.1402 g
1 mg = 0.001 g
Moles of calcium oxalate = 
1 mole of calcium oxalate have 1 mole of calcium atom.
Then 0.001095 moles of calcium oxalate will have 0.001095 moles of calcium atom.
Mass of 0.001095 moles of calcium :
0.001095 mol × 40 g/mol = 0.04381 g
Mass of sample of limestone = 128.3 mg = 0.1283 g
Percentage of calcium in limestone:
34.15% is the mass percentage of calcium in the limestone.
Explanation:
To find the amount of product that would be formed from two or more reactants, we need to follow the following steps;
- Find the number of moles of the given reactants.
- Then proceed to determine the limiting reactant. The limiting reactant is the one in short supply which determines the extent of the reaction.
- Use the number of moles of the limiting reactant to find the number of moles of the product.
- Then use this number of moles to find the mass of the product
Useful expression:
Mass = number of moles x molar mass
We subtract the enthalpies of the reactants from that of the products:
Since this is < 0, this is an exothermic reaction.
Answer: P2O5
Explanation: You divide both subscripts by 2 to get the empirical formula.
Answer:
B 144.0 s is the best answer of this question
