For the reaction
2
agno

3
+
na

2
cro

4
⟶
ag

2
cro

4
+2
nano

3
2agno3+na2cro4⟶ag2cro4+2nano3
how many grams of sodium chromate, na2cro4, are needed to react completely with
12.1
12.1
g of silver nitrate, agno3?

Mass of Na₂CrO₄ =  5.75 g

Explanation:

First of all we will write the balance chemical equation.

2AgNO₃ + Na₂CrO₄     →    Ag₂CrO₄  +  2NaNO₃

Now we will calculate the moles of AgNO₃.

Number of moles = mass / molar mass

Molar mass of AgNO₃ = 107.87 + 14 + 3× 16 =  169.87 g/mol

Number of moles = mass / molar mass

Number of moles = 12.1 g / 169.87 g/mol = 0.071 mol

Now we will compare the moles of AgNO₃ and  Na₂CrO₄ from balance chemical equation.

                        AgNO₃    :     Na₂CrO₄

                          2            :           1

                          0.071     :           1/2× 0.071 = 0.0355

Now we will calculate the mass of Na₂CrO₄.

Molar mass of Na₂CrO₄ = 23×2 + 52 + 16×4 = 162 g/mol

Mass of Na₂CrO₄ = number of moles  ×  molar mass

Mass of Na₂CrO₄ =  0.0355 mol ×  162 g/mol

Mass of Na₂CrO₄ =  5.75 g

h

plants need sunlight, water, and carbon dioxide to make food. plants use the raw materials of water, nutrients they absorb from soil, and carbon dioxide to make sugars the plant can use. energy from the sun and chlorophyll are also needed.