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.
Fusion power is the power generated by nuclear fusion processes. In fusion reactions, two light atomic nuclei fuse together to form a heavier nucleus. In doing so, they release a comparatively large amount of energy that arises from the binding energy, creating an increase in temperature of the reactants.
The question is incomplete, the complete question is;
An alcohol thermometer makes use of alcohol's changing _______ in order to measure temperature. As the temperature goes up, the alcohol contained in the thermometer increases in volume, filling more of the thermometer's tube.
A.
mass
B.
state
C.
chemical composition
D.
density
Answer:
D.
density
Explanation:
Every kind of thermometer makes use of a change in a particular physical property of a substance as a measure of temperature. It must be a property that changes with temperature.
Density of a substance changes with temperature. Even though the mass of alcohol in glass remains constant, but its volume increases or decreases with change in temperature leading to a change in volume and consequently a change in density of the alcohol in glass. This change is used as a measure of the change in temperature.
Answer:
Empirical formulas can be determined from the percent composition of a compound. In order to determine its molecular formula, it is necessary to know the molar mass of the compound. Chemists use an instrument called a mass spectrometer to determine the molar mass of compounds.
