The answer would be D. The only minerals harder than corundum is diamond.
Answer:
Zn+2HCl→ZnCl2+H2
Explanation:
Hydrogen gas is prepared in the laboratory by reacting dilute HCl with granulated zinc.
Chlorine. Electronegativity rises as you go up and to the right on the periodic table.
Burning charcoal is a chemical reaction called combustion
Answer:
"500 Joule/sec" is the right answer.
Explanation:
The given values are:
Force,
F = 1000 N
Velocity,
s = 10 m
Time,
t = 20 s
Now,
The power will be:
= 
On putting the values, we get
= 
= 
= 