# Chemistry

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mass-mass conversions and mass-mole conversions: what is the difference and how do you do each?

mass is converted to mols by mols = grams/molar mass.

mass of one chemical is converted to mass of another chemical by using the coefficients in the balanced chemical equation. For example:

CH4 + 2O2 ==> CO2 + 2H2O

16 grams CH4 converts to how many grams CO2. The molar mass CH4 is 16; the molar mass CO2 is 44.

mols CH4 = 16/16 = 1 mol
Now convert mols CH4 to mols CO2.

mols CO2=mols CH4 x (1 mol CO2/1 mol CH4) [note that I used the coefficients in the balanced equation for the coefficients in the factor of 1 mol CO2/1 mol CH4].

Now convert mols CO2 to grams CO2.
grams = mols x molar mass
grams CO2 = mols CO2 x molar mass CO2.
g CO2 = 1 x 44 = 44 g CO2.

I hope this helps.

it does- thank you so much!

in a mass-mass conversion you are given a certain amount of an elemnt in grams and you are asked to fid the mass of another substance in the balance equatin that you are given.

For example:
they want you to find the mass of water in the chemical equation in which glucose is changed to water and carbon dioxide.
C6H12O6+6O2 ARROW 6CO2+6H2O
you are given the mass of glucose 1.5g
1)convert 1.5g of glucose into moles
1.5g C6H12O6 x 1 mol of C6H12O6
divided by 180g glucose
*the 180g of glucose you get thjem from their atomic mass unit in the periodic table, you add them.
2)in step 1) you get 0.0083molC6H12O6 this multiply it by the # of moles of water H2O that are per each mole of glucose wich is six. so multiply 0.0083 by and you get 0.05 mol H2O.
3)now convert this moles of water to grams of water by multiplyng them by the mass of water, this will give you 0.9g of water and that is the result.

the mass-mole are the smae but without the 3) step

• Chemistry -

the reaction between X and Y started at 1.00kj and the product of XY was formed at 10.00kj; draw the energy profile for the reaction