Answer:
The characteristics of cathode rays do not depend upon the material of electrodes and the nature of the gas present in the cathode ray tube.
Answer:
5200 ppm
Explanation:
As per the definition, parts per million of a contaminant is a measure of the amount of mass of contaminant present per million amount of the solution. It is denoted by ppm.
Given in the question,
Water = 250 ml = 250 g
Lead = 1.30 g
So,
ppm of Lead = 
= 
= 5200 ppm
So, as calculated above, there is 5200 ppm of lead present in 250 ml of water.
So what am I suppose to answer here?
Answer:
294.87 gm CaCl_2
Explanation:
The computation of the mass of calcium chloride is shown below:
But before that following calculations need to be done
Number of moles of chlorine atom is
= 3.20 × 10^24 ÷ 6.022 × 10^23
= 5.314 moles
As we know that
1 mole CaCl_2 have the 2 moles of chlorine atoms
Now 5.341 mole chloride atoms would be
= 1 ÷ 2 × 5.314
= 2.657 moles
Now
Mass of CaCl_2 = Number of moles × molar mass of CaCl_2
= 2.657 moles × 110.98 g/mol
= 294.87 gm CaCl_2
