How many gramsof sodium carbonate are neededto make1.30l of0.890m

Do you mean 0.890 m or 0.890 M?

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To determine the amount of sodium carbonate needed to make a solution of a certain molarity, you will need to use the formula:

Molarity = moles / volume

Given:
Molarity = 0.890 M
Volume = 1.30 L

First, we need to calculate the number of moles of sodium carbonate using the equation:

moles = Molarity * volume

Plugging in the values:

moles = 0.890 M * 1.30 L

Now, to calculate the mass of sodium carbonate, we need to use the equation:

mass = moles * molar mass

The molar mass of sodium carbonate (Na2CO3) is calculated by adding up the atomic masses of each element in the compound:

Molar mass of Na2CO3 = (2 * atomic mass of Na) + atomic mass of C + (3 * atomic mass of O)

Consulting the periodic table, we find:

Atomic mass of Na = 22.99 g/mol
Atomic mass of C = 12.01 g/mol
Atomic mass of O = 16.00 g/mol

Now we can calculate the molar mass:

Molar mass of Na2CO3 = (2 * 22.99 g/mol) + 12.01 g/mol + (3 * 16.00 g/mol)

Finally, we can calculate the mass of sodium carbonate:

mass = moles * molar mass

Now you can substitute the values you have obtained into the equation to find the answer.