Reaction equation:
K₂CrO₄(aq) + PbCl₂(aq) → 2KCl(aq) + PbCrO₄(s)
Concentration = moles / Liter
moles(K₂CrO₄) = 3 x 0.025
= 0.075
By the equation, we see that the molar ratio of
K₂CrO₄ : PbCrO₄ is
1 : 1
moles(PbCrO₄) = 0.075
mass = moles x Mr
mass = 0.075 x (207 + 52 + 16 x 4)
mass = 24.2 grams
<h3>
Answer:</h3>
63 years
Eighth
The number of half lives
<h3>
Explanation:</h3>
It will take 63 years for half of the sample to decay
In 189 years, eighth of the sample will be left
Scientists can figure out how old a sample is by multiplying the number of half lives by the length of the half life.
Half life is the time taken by a radioactive sample to decay to half of the original amount.
Therefore, for a radioactive element with a half-life of 63 years, it will take 63 years for the sample to decay to half of the original amount.
After 189 years, only an eighth of the sample will be left.
That is, 189 years is equivalent to 3 half-lives
Therefore, if the original amount is 1, then;
1 → 0.5 → 0.25 → 0.125
Thus, scientists can figure out how old a sample is by multiplying the number of half lives by the length of the half life.
Electrons are shared in compound X and transferred in compound Y.
<h3>Further explanation </h3>
1. ionic bonding
Bonding that occurs due to electron transfer. Can occur in metal and non-metal atoms. To get stability, atoms release or bind electrons to get stable electron regulation from noble gases
2. covalent bonding
Bonding that occurs due to shared use of electron pairs
The two bound atoms contribute their electrons to produce bonds
Generally occurs in non-metallic elements
So compound X = covalent bond (metal with metal) and compound Y= ionic bond(metal with non metal)
- Compound X : shared electron
- Compund Y : transferred electron
