Lewis dot structure for phosphorus
Answer:
Time taken 172.8 years
Explanation:
Given data:
Total amount of strontium-90 = 1000.0 g
Amount left = 15.625 g
Half life of strontium = 28.8 years
Time taken = ?
Solution:
Number of half lives:
At time zero = 1000.0 g
At first half life = 1000.0g/2 = 500 g
At second half life = 500 g/2 = 250 g
At third half life = 250 g/ 2 = 125 g
At 4th half life = 125 g/ 2= 62.5 g
At 5th half life = 62.5 g/2 = 31.25 g
At 6th half life = 31.25 g / 2 = 15.625 g
Time taken:
Time taken = number of half lives × half life
Time taken = 6×28.8 years
Time taken = 172.8 years
Answer:
A 0.239mol
Explanation:
From the equation:
We were given that 10g of iron was involved in this chemical reaction
We can establish that :
3moles of Fe would produced 4 moles of Hydrogen gas
Therefore:
Number of moles of iron = mass of Fe / mloar mass of iron
Mass of Fe = 10g
Molar Mass of Fe = 55.85g/mol
Therefore, number of moles of iron= 10/55.85
Number of moles of iron = 0.179mol
3moles of Fe would produced 4 moles of Hydrogen gas
So, 0.179mol of Fe would give 0.179x4/3
The number of mole of Hydrogen gas produced is 0.239mol.
Answer:

Explanation:
Bases are the species which furnish hydroxide ions in the solution or is capable of forming bonds with electron deficient species as they are electron rich species. When a base accepts a proton, it changes into a acid which is known as its conjugate acid.
Net ionic equation : In the net ionic equations, we are not include the spectator ions in the equations. Only the species which are present in aqueous state dissociate. So, the net ionic equation of aqueous solution of ammonia is shown below as:-
