The correct answer would b C
To convert the given number of moles of aluminum to grams, we need to use the molar mass of the element as the conversion factor. Aluminum has a molar mass of 26.981 g/ mol. The answer to this problem is b. <span>fraction: 26.981 g Al over one mol Al. </span>
Answer:
(C) Mass of KCl(s), mass of H20, initial temperature of the water, and final temperature of the solution
Explanation:
molar enthalpy of solution of KCl(s) is heat evolved or absorbed when one mole of KCl is dissolved in water to make pure solution . The heat evolved or absorbed can be calculated by the following relation.
Q = msΔt where m is mass of solution or water , s is specific heat and Δt is change in temperature of water .
So data required is mass of water or solution , initial and final temperature of solution , specific heat of water is known .
Now to know molar heat , we require mass of solute or KCl dissolved to know heat heat absorbed or evolved by dissolution of one mole of solute .
Answer:
When we compare the two solids, we see that quartz is a crystalline solid with relatively long-range order and glass is amorphous solid with short range order and has a tendency to flow. When quartz is heated, it can be easily converted into glass.
Answer:- 0.134 seconds
Solution:- The speed is given as 
and the circumference is 24900 miles which is same as the distance light have to covered. It asks to calculate the time required to cover this distance by the light.
We need to do unit conversion from miles to meter as the speed is given in meter per second.
1 mile = 1609.34 meter
So, 
= 40072566 meters
Know that, 
It's rearranged to time as, 
Let's plug in the values in it:
= 0.134 seconds
So, the light would take 0.134 seconds to travel the mentioned speed. The answer without the unit is 0.134.
