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3 years ago

C. How many grams of Na2SiO3 can react with 0.800 g of HF?

Chemistry

1 answer:

finlep [7]3 years ago

5 0

Answer:

Mass = 0.610 g

Explanation:

Given data:

Mass of Na₂SiO₃ = ?

Mass of HF = 0.800 g

Solution:

Chemical equation:

Na₂SiO₃ + 8HF → H₂SiF₆ + 2NaF + 3H₂O

Number of moles of HF:

Number of moles = mass/ molar mass

Number of moles = 0.800 g/ 20 g/mol

Number of moles = 0.04 mol

Now we will compare the moles of HF and Na₂SiO₃.

HF : Na₂SiO₃

8 : 1

0.04 : 1//8×0.04 = 0.005

Mass of Na₂SiO₃:

Mass = number of moles × molar mass

Mass = 0.005 mol × 122.07 g/mol

Mass = 0.610 g

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4 years ago

The lowest possible concentration of free hydrogen ions is represented by a ph value of

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3 years ago

An iron ore sample weighing 0.5562 g is dissolved HCl (aq), and the iron is obtained as Fe2 in solution. This solution is then t

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Answer:

$\% Fe^{+2}=70%$

Explanation:

Hello,

In this case, we could considering this as a redox titration:

$Fe^{+2}+(Cr_2O_7)^{-2}\rightarrow Fe^{+3}+Cr^{+3}$

Thus, the balance turns out (by adding both hydrogen ions and water):

$Fe^{+2}\rightarrow Fe^{+3}+1e^-\\(Cr_2^{+6}O_7)^{-2}+14H^++6e^-\rightarrow 2Cr^{+3}+7H_2O\\\\6Fe^{+2}+(Cr_2^{+6}O_7)^{-2}+14H^++6e^-\rightarrow Cr^{+3}+7H_2O+6Fe^{+3}+6e^-$

Thus, by stoichiometry, the grams of Fe+2 ions result:

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3 years ago

How many electrons will each element gain or lose in forming an ion?

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3 years ago

Empirical formula of a compound composed of 32.1 g potassium (k) and 6.57 g oxygen (o)?

tester [92]

The empirical formula is K₂O.

The empirical formula is the simplest whole-number ratio of atoms in a compound.

The ratio of atoms is the same as the ratio of moles.

So, our job is to calculate the molar ratio of K to O.

Step 1. Calculate the moles of each element

Moles of K = 32.1 g K × (1 mol K/(39.10 g K =) = 0.8210 mol K

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Step 2. Calculate the molar ratio of each element

Divide each number by the smallest number of moles and round off to an integer

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Step 3: Write the empirical formula

EF = K₂O

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3 years ago