In an exothermic reaction, heat is produced along with products. But in endothermic reaction, heat is absorbed. If the number of products is less than the sum of the enthalpies of the reactants, the reaction will be exothermic. If the number of products is more than the sum of the enthalpies of the reactants, the reaction is endothermic.
Answer:
atoms of hydrogen are there in
35.0 grams of hydrogen gas.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number
of particles.
To calculate the moles, we use the equation:
1 mole of hydrogen
=
atoms
17.5 mole of hydrogen
=
atoms
There are
atoms of hydrogen are there in
35.0 grams of hydrogen gas.
Look at the liter man it’s a great way to learn how much every liquid measurement is
Sugar is a compound.
<span>C12H22O<span>11</span></span>
Answer: 17) d. ![C_2H_6](https://tex.z-dn.net/?f=C_2H_6)
18. c. The empirical formula of a compound can be twice the molecular formula.
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
To calculate the molecular formula, we need to find the valency which is multiplied by each element to get the molecular formula.
The equation used to calculate the valency is:
![n=\frac{\text{molecular mass}}{\text{empirical mass}}](https://tex.z-dn.net/?f=n%3D%5Cfrac%7B%5Ctext%7Bmolecular%20mass%7D%7D%7B%5Ctext%7Bempirical%20mass%7D%7D)
The empirical mass can be calculated from empirical formula and molar mass must be known.
17. Thus the empirical formula of
should be ![CH_3](https://tex.z-dn.net/?f=CH_3)
18. The molecular formula will either be same as empirical formula or is a whole number multiple of empirical formula. Thus the empirical formula of a compound can never be twice the molecular formula.