Answer:
11
Explanation:
Data obtained from the question include:
Mass number = 23
Neutron = 12
Atomic number =.?
Next, we shall determine the number of protons present in the element.
This can be achieved by doing the following:
Mass number = Proton + Neutron
Mass number = 23
Neutron = 12
Proton =...?
Mass number = Proton + Neutron
23 = Proton + 12
Collect like terms
Proton = 23 – 12
Proton = 11
The atomic number of an element is equal to the proton number.
Atomic number = proton number
Proton number = 11
Atomic number = proton = 11
Therefore, the atomic number is 11.
Answer:
K₂CrO₅
Explanation:
The empirical formula is the simplest formula of a compound. To find the empirical formula, we follow the procedure below:
Elements Potassium Chromium Oxygen
Mass 6.52 4.34 5.34
Molar mass 39 60 16
Number of moles 6.52/39 4.34/60 5.34/16
0.167 0.072 0.333
Divide through by
the smallest 0.167/0.072 0.072/0.072 0.333/0.072
2.3 1 4.6
2 1 5
Empirical formula K₂CrO₅
Answer:
Explanation:
1 . Write the chemical equation.
2 . Calculate the moles of product from the first reactant.
3 . Calculate the moles of product from the second reactant.
4 . Identify the limiting reactant and the excess reactant.
5 . Calculate the mass of excess reactant used up.
6 . Calculate the mass of unused excess reactant.
7 . Calculate the mass of limiting reactant needed to react with the 8 . unused excess reactant.
<span>causing disruption or annoyance through being unwelcome or uninvited.</span>
