Answer:
D. only 2 and 3
Explanation:
The Grignard compound or reagent is a highly reactive compound formed from the reaction between an ether solvent containing magnesium and a haloalkane. This compound can also be used to create a C-C bond (carbon-carbon). Based on the properties and structure of a Grignard compound, the answer is option D.
Answer: ethylene glycol (molar mass = 62.07 g/mol)
Explanation:
Depression in freezing point :
Formula used for lowering in freezing point is,

or,

where,
= change in freezing point
= freezing point constant= 
m = molality
Given mass of solute = 0.807 g
Molar mass of solute=? g/mol
weight of solvent in kg= 11.6 g=0.0116 kg



Thus the solute is ethylene glycol which has same molecular mass as calculated, i.e 62.07 g/mol.
Answer:
The history of water supply and sanitation is one of a logistical challenge to provide clean water and sanitation systems since the dawn of civilization. Where water resources, infrastructure or sanitation systems were insufficient, diseases spread and people fell sick or died prematurely.
Explanation:
It is greater than the total mass of the products