The moon affects the tides and water levels
Answer: Option (c) is the correct answer.
Explanation:
Wood is a mixture of different substances. Primarily it consists of cellulose, lignin, water etc.
When we heat wood then all these substance oxidize into the atmosphere even before they could melt.
Whereas iron, sodium chloride and ethanol all are the substances which can melt at any temperature.
Thus, we can conclude that out of the given options, wood, a mixture of different substances is a material that does not melt at any temperature.
Strontium has four stable, naturally occurring isotopes: 84-Sr (0.56%), 86-Sr (9.86%), 87-Sr (7.0%) and 88-Sr (82.58%). 87.62 is standard atomic mass of strontium.
When the concentration is expressed in ppm, that means parts per million. It is also equivalent to mg/L. For this problem, we do stoichiometric calculations. We manipulate the units by cancelling like units if they appear in the numerator and denominator side until we come with the amount of solid Ca(OCl)2 needed. The solution is as follows:
40 mg/L * (1 L/1000 mL) * 50 mL * (1 g/1000 mg) * (1 mol OCl⁻/51.452 g) * (1 mol Ca(OCl)₂/ 2 mol OCl⁻) * (142.983 g Ca(OCl)₂/mol) * 0.95 = 2.64×10⁻3 g or 2.64 mg.
Therefore, you would need 2.64 mg of solid Ca(OCl)₂.