There is no temperature at all shown below. Is that the same as Absolute Zero ?
<u>Answer:</u> The mass of sucrose required is 69.08 g
<u>Explanation:</u>
To calculate the concentration of solute, we use the equation for osmotic pressure, which is:

Or,

where,
= osmotic pressure of the solution = 8.80 atm
i = Van't hoff factor = 1 (for non-electrolytes)
Mass of solute (sucrose) = ?
Molar mass of sucrose = 342.3 g/mol
Volume of solution = 564 mL (Density of water = 1 g/mL)
R = Gas constant = 
T = Temperature of the solution = 290 K
Putting values in above equation, we get:

Hence, the mass of sucrose required is 69.08 g
What you are looking for is something from the left side of the periodic table (the metals), combined with something from the right side of the periodic table.
SiCl4 is something from the middle with something on the right. Not the answer.
HCl is a possible answer, but it is not the best one, because Hydrogen can be on both sides. It is not quite as willing to give up its electrons as the answer.
CCl4 has the same problem as A.
The answer is C
Ca is in column 2 just about as far left as you can get.
Cl is in column 17 which is just about as far right as you can get.
Answer:
The mixture of B and C will melt as 130 - 139 ºC.
Explanation:
If the melting point (130 - 139 ºC) of a mixture of A and B is lower than the pure substances that is 149 - 150 ºC that means that one of these susbtances is an impurity because reduces the melting point.
If the melting point of the mixture of A and C is the same as the pure substances, we can deduce that they are the same substances, also because the melting point when a substance is pure is just 1 or 2 ºC like in this case.
So in a Mixture of B and C is going to be like the first case of the mixture among A and B, because the B substance is the impurity.