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PtichkaEL [24]
2 years ago
10

Why were gold and copper the first forms of matter investigated by humans

Chemistry
1 answer:
baherus [9]2 years ago
8 0
They were valuable to the eyes of man then.
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The following equation shows the correct molecules formed in the reaction, but the products are incorrect. CH4 +202=H20+ CO2 How
Hunter-Best [27]
For the equation to balance out, you would need 2 H2O on the product. That will give a total of 1 Carbon, 4 Hydrogens and 4 Oxygens on each side.
5 0
3 years ago
20 moles of NH3 are needed to produce ? Moles of H2O
AfilCa [17]

Hi :)

20 mol NH3 x 6 H2O/4 NH3 = 30 mol H2O

Hope this helped :)

5 0
3 years ago
Consider the following equilibrium: 4KO2(s) + 2H2O(g) 4KOH(s) + 3O2(g) Which of the following is a correct equilibrium expressio
jeka57 [31]
To be able to write correctly the equilibrium expression of a reaction, we need to know the balanced reaction and the phases of the substances in the reaction. When substances are solid, pure liquid they are not included in the expression. We do as follows:

<span>4KO2(s) + 2H2O(g) = 4KOH(s) + 3O2(g)

K = [O2]^3 / [H2O]^2</span>
5 0
3 years ago
Consider the following reaction between calcium oxide and carbon dioxide: CaO(s)+CO2(g)→CaCO3(s) A chemist allows 14.4 g of CaO
sweet-ann [11.9K]

Answer:

Theoretical yield =26.03 g

Percent yield = 87%

Limiting reactant = CaO

Explanation:

Given data:

Mass of CaO = 14.4 g

Mass of CO₂ = 13.8 g

Actual yield of CaCO₃ = 22.6 g

Theoretical yield = ?

Percent yield = ?

Limiting reactant = ?

Solution:

Chemical equation:

CaO + CO₂   → CaCO₃

Number of moles of CaO:

Number of moles  = Mass /molar mass

Number of moles = 14.4 g / 56.1 g/mol

Number of moles  = 0.26 mol

Number of moles of CO₂:

Number of moles = Mass /molar mass

Number of moles = 13.8 g / 44 g/mol

Number of moles = 0.31 mol

Now we will compare the moles of CO₂ and CaO with CaCO₃ .

                  CO₂         :                CaCO₃  

                  1               :                 1

                 0.31           :              0.31

                CaO           :               CaCO₃  

                 1                :                 1

                 0.26         :              0.26

The number of moles of  CaCO₃ produced by CaO are less it will be limiting reactant.

Mass of CaCO₃: Theoretical yield

Mass of CaCO₃ = moles × molar mass

Mass of CaCO₃ =0.26 mol × 100.1 g/mol

Mass of CaCO₃ =  26.03 g

Percent yield:

Percent yield = actual yield / theoretical yield × 100

Percent yield = 22.6 g/ 26.03 g × 100

Percent yield = 0.87× 100

Percent yield = 87%

Limiting reactant:

The number of moles of  CaCO₃ produced by CaO are less it will be limiting reactant.

7 0
3 years ago
How many liters of salt solution will be needed to provide 15 grams of salt if the concentration of the solution is 50 g/l?​
asambeis [7]

Answer:

.30 l

Explanation:

15g/50g/l= .3l

6 0
2 years ago
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