Calculate the formula unit mass of nahco3. (at. mass of na=23u, h=1u, c=12u, o=16u)

Formula unit mass of is 84 u.

Explanation:

Formula unit mass can be calculated by the adding individual element mass in the formula of the compound.

The given compound -

From the given the atomic mass of each element in the given compound is as follows.

Atomic mass of sodium (Na) = 23 u

Atomic mass of Hydrogen (H) = 1 u

Atomic mass of carbon (c) = 12 u

Atomic mass of oxygen (O) = 16 u

The number of atoms in the formula:

1 sodium atom =23 u

1 hydrogen atom = 1 u

1 carbon atom =  12 u

3 oxygen atom = 3 X 16 u = 48 u

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Formula mass = 84 u

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Therefore, Formula unit mass of is 84 u.

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.