The mass of a nickel coin is 5 g.
1 mol of Ni weighs 58 g. 1 mol contains 6.022 x 10²³ atoms of Ni.
therefore in 58 g there are 6.022 x 10²³ atoms of Ni
then in 5 g the number of Ni atoms are - 6.022 x 10²³ /58 x 5 = 5.2 x 10²² Ni atoms
Therefore number of Ni atoms are 5.2 x 10²² atoms in a nickel coin
Answer:
22.44°C will be the final temperature of the water.
Explanation:
Heat lost by tin will be equal to heat gained by the water

Mass of tin = 
Specific heat capacity of tin = 
Initial temperature of the tin = 
Final temperature =
=T

Mass of water= 
Specific heat capacity of water= 
Initial temperature of the water = 
Final temperature of water =
=T



On substituting all values:

we get, T = 22.44°C
22.44°C will be the final temperature of the water.
Answer:
They are called insulators
Answer:
a. blue, b. red, c. red, d. basic - blue
Explanation:
a.washing powder ( containing sodium carbonate ) basic -blue
b. orange juice ( containing citric acid )- acidic -red
c. lemonade ( containing H2CO₃ )-acidic - red
d. cleaner ( containg NH₃ )- basic - blue