How many photons are produced in a laser pulse of 0.430j at 679nm.
2 answers:
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Answer:
Explanation:
From the given information:
mass of silver chloride AgCl = 11.89 g
molar mass of AgCl = 143.37 g/mol
We know that:
number of moles = mass/molar mass
∴
number of moles of AgCl = 11.89 g/ 143.37 g/mol
number of moles of AgCl = 0.0829 mol
The chemical equation for the mineral called trona is:
when being reacted with hydrochloric acid, we have:
One mole of NaCl formed from one mole of trona sample = 0.0829 moles of AgCl
i.e. 0.0829 moles of NaCl can be formed from AgCl
mass of trona sample = number of moles × molar mass
mass of trona sample = 0.0829 × 226
mass of trona sample = 18.735 g
The mass in the percentage of NaHCO₃ = mass of NaHCO₃/ mass of trona
The mass in the percentage of NaHCO₃ = 6.93/18.735
The mass in the percentage of NaHCO₃ = 0.36989
The mass in the percentage of NaHCO₃ = 36.99%
Nonetheless, a 6.78 g samples manufactured from sodium carbonate in pure 100%
∴
6.78 g sample manufactured from Na₂CO₃ is purer.
Answer:
30.8 grams of magnesium hydroxide will form from this reaction, and magnesium nitrate is the limiting reagent.
Explanation:
The reaction that takes place is:
- 2NaOH + Mg(NO₃)₂ → 2NaNO₃ + Mg(OH)₂
Now we <u>convert the given masses of reactants to moles</u>, using their respective <em>molar masses</em>:
- 68.3 g NaOH ÷ 40 g/mol = 1.71 mol NaOH
- 78.3 g Mg(NO₃)₂ ÷ 148.3 g/mol = 0.528 mol Mg(NO₃)₂
0.528 moles of Mg(NO₃)₂ would react completely with (0.528 * 2) 1.056 moles of NaOH. There are more than enough NaOH moles, so NaOH is the reagent in excess and <em>Mg(NO₃)₂ is the limiting reagent.</em>
Now we <u>calculate how many Mg(OH)₂ are produced</u>, using the <em>moles of the limiting reagent</em>:
- 0.528 mol Mg(NO₃)₂ *
= 0.528 mol Mg(OH)₂
Finally we convert Mg(OH)₂ moles to grams:
- 0.528 mol Mg(OH)₂ * 58.32 g/mol = 30.8 g