Hiw many moles of 12c in 3.50g

How many moles are in 17.2g k2s

Natalija [7]

Answer: 0.156 mol

Explanation:

To find the moles of 17.2 g K₂S, we need to know the molar mass to convert.

$17.2g*\frac{mol}{110.256 g} =0.156 mol$

3 0

3 years ago

How many grams of CaCl2 are in 250 mL of 2.0 M CaCl2?

Tom [10]

The answer is: " 56 g CaCl₂ " .
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Explanation:
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2.0 M CaCl₂ = 2.0 mol CaCl₂ / L ;

Since: "M" = "Molarity" (measurement of concentration);

= moles of solute per L {"Liter"} of solution.
__________________________________________________________
Note the exact conversion: 1000 mL = 1 L .

Given: 250 mL ;

250 mL = ? L ? ;

250 mL * (1 L / 1000 L) = (250/1000) L = 0.25 L .
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(2.0 mol CaCl₂ / L ) * (0.25L) = (2.0) * (0.25) mol = 0.50 mol CaCl₂ ;

We have: 0.50 mol CaCl₂ ; Convert to "g" (grams):

→ 0.50 mol CaCl₂ .
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1 mol CaCl₂ = ? g ?

From the Periodic Table of Elements:

1 mol Ca = 40.08 g

1 mol Cl = 35.45 g .

There are 2 atoms of Cl in " CaCl₂ " ;

→ Note the subscript, "2", in the " Cl₂ " ;
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So, to calculate the molar mass of "CaCl₂" :

40.08 g + 2(35.45 g) =

40.08 g + 70.90 g = 110.98 g ; round to 4 significant figures;

→ round to 111 g/mol .
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So:

→ 0.50 mol CaCl₂ = ? g CaCl₂ ? ;

→ 0.50 mol CaCl₂ * (111 g CaCl₂ / mol CaCl₂) ;

= (0.50) * (111 g) CaCl₂ ;

= 55.5 g CaCl₂ ;

 → round to 2 significant figures;

 → 56 g CaCl₂ .
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The answer is: " 56 g CaCl₂ " .
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6 0

3 years ago

Read 2 more answers

Sodium metal is quiet soft whereas sodium chloride crystals are quiet hard explain why

stiks02 [169]

In mineralogy and crystallography, a crystal structureis a unique arrangement of atoms in a crystal. Acrystal structure is composed of a unit cell, a set of atoms arranged in a particular way; which is periodically repeated in three dimensions on a lattice.
Crystals create a harder more fitting structure so they tend to be a lot stronger than other compounds or elements

8 0

4 years ago

What is the net Ionic equation of HClO4(aq)+ NaOH(aq) = H2O(l)+ NaClO4(aq)

uranmaximum [27]

H^+(aq) + OH^-(aq) ---> H2O(l)

Na^+ and ClO4^- are the spectator ions.

7 0

3 years ago

Lead(II) oxide from an ore can be reduced to elemental lead by heating in a furnace with carbon. Calculate the expected yield of

Lelu [443]

Answer:

53kg is the expected yield of lead

Explanation:

Firstly, in order to solve this question, we need to write the equation of reaction correctly. This is as follows:

PbO(s) + C(s) ---> Pb(l) + CO(g)

We proceed from here. We should get the limiting reactant but this can only be obtained by getting the number of moles of each reactant present.

The formula to use across all boards is that the number of moles is the mass of each of the reactant divided by the molar mass of each of the reactant.

For PBO, mass is 57kg = 57000g

Molar mass of PBO = 223.20g/mol

The number of moles is thus 57,000/223.2 = 255.37 moles

For carbon, mass is also 57kg = 57000g

Molar mass is 12g/mol

Number of moles of carbon = 57000/12 = 4750 moles

From the number of moles, we can see that the number of moles of Carbon is greater than that of PbO. This means that PbO is the limiting reagent.

Hence we use it to calculate percentage yield.

The number of moles of lead formed is the same of number of moles of lead oxide = 255.37 since we have mole ratio of 1 to 1

The molar mass of lead is 207.20g/mol

The mass of lead formed is = moles of lead formed * molar mass of lead = 207.20 * 255.37 = 52,912g which is approximately 53kg

Hence the expected yield is 53kg

6 0

3 years ago