Explanation:
A volatile substance is defined as the substance which can easily evaporate into the atmosphere due to weak intermolecular forces present within its molecules.
Whereas a flammable substance is defined as a substance which is able to catch fire easily when it comes in contact with flame.
Hence, when we heat a flammable or volatile solvent for a recrystallization then it should be kept in mind that should heat the solvent in a stoppered flask to keep vapor away from any open flames so that it won't catch fire.
And, you should ensure that no one else is using an open flame near your experiment.
Thus, we can conclude that following statements are correct:
- You should heat the solvent in a stoppered flask to keep vapor away from any open flames.
- You should ensure that no one else is using an open flame near your experiment.
Answer:
1. observations
2. hypothesis
3. experimentation
Explanation:
Observations are made, Hypothesies are formed from observations, and experimnets help alter and comfirm hypothesis.
Molarity is expressed as
the number of moles of solute per volume of the solution. For example, we are
given a solution of 2M NaOH this describes a solution that has 2 moles of NaOH
per 1 L volume of the solution. We calculate as follows:
0.115 M = n mol KBr / .55 L solution
n = 0.06325 mol KBr
mass = 0.06325 mol KBr (119 g / mol) = 7.53 g KBr
1 mole of carbon contains 12 g
Thus, 34.6 moles will contain; 34.6 × 12 = 415.2 g
If a substance contains 89.2 % carbon,
then, (415.2/89.2) ×100 = 465.47 g of the substance will be required to yield 34.6 moles of carbon.
Check attached file for the answer.
