Answer:
1 is c 2 is b
Explanation:
because atomic number is the number of protons in a nucleus
2..because the number of protons plus number of neutrons is equal to mass number.
For H2O(l) at 100 ∘C, d=0.958gcm−3 and ΔvapH=40.7kJmol−1.
Answer:

Explanation:
mass of Fe = 55.85 g
Molar mass of Fe = 55.85 g/mol
<u>Moles of Fe = 55.85 / 55.85 = 1</u>
mass of Cl = 106.5 g
Molar mass of Cl = 35.5 g/mol
Moles of Cl = 106.5 / 35.5 = 3
Taking the simplest ratio for Fe and Cl as:
1 : 3
The empirical formula is = 
Crystals impurities are expected to have high solubility in cold solvents. Hence, option C is correct.
<h3>What is a cold solvent?</h3>
Cold solvent cleaning is a process used to remove grease, wax and other impurities from metal and other parts.
The process is also called degreasing. Cold solvents are sprayed onto the dirty part and it is brushed clean.
Once the filtration process is done the collected crystals should be washed with a little more ice-cold solvent to remove final soluble impurities which would otherwise be left on the surface of the crystals.
Hence, option C is correct.
Learn more about the cold solvent here:
brainly.com/question/11445831
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