Answer:
The correct answer is - 9935 years approximately.
Explanation:
Let z be the age in years to be found:
(15300 disintegrations) x (1.0 g / 0.250 g) / (1.84×10^4 disintegrations)
= 3.3260
half life of carbon = (1/2)^(z/5730 yr)
Solve for z
3.3260 = (1/2)^(z/5730)
Take the log of both sides:
log 3.3260 = (z/5730) log (1/2)
log 3.3260 / log (1/2) = z/5730
z = 5730 log 3.3260 / log (1/2)
= 1.73378816*5730
= 9935 years approximately.
The balanced chemical equation for reaction of 
and 
is as follows:
From the balanced chemical equation, 2 mol of reacts with 1 mol of 
.
First calculating number of moles of as follows:
On rearranging,
Here, M is molarity and V is volume. The molarity of is given 0.274 M or mol/L and volume 155 mL, putting the values,
Since, 1 mol of reacts with 2 mol of thus, number of moles of will be 
.
Now, molarity of is given 0.305 M or mol/L thus, volume can be calculated as follows:
Therefore, volume of is 278.5 mL.
Answer:
Using dimensional analysis:
3.01x1022 molecules CO2 x 1 mol CO2/6.02x1023 molecules x 44. g CO2/mole = 2.20 g CO2
Explanation:
Answer:
The correct answer is - B. dissolving → evaporation filtration → crystallisation
Explanation:
The method of the preparation of a pure sample of copper(II) sulfate from dilute sulfuric acid and copper II oxide is given as follows:
step 1. Adding dilute sulfuric acid into a beaker. Using bunsen burner heat the beaker.
step 2. Adding the copper (II) oxide into the beaker and give it a little time at a time to the warm dilute sulfuric acid and stir
step 3. Filtering the mixture into an evaporating vessel to remove the excess copper (II) oxide and water from the filtrate.
Step 4. leave the rest filtrate to crystallize.
Copper (II) Oxide {CuO (s)} + Dilute Sulfuric Acid {H2SO4 (aq)} → Copper (II) Sulphate {CuSO4 (s)} + Water {H2O}
