The third reaction will form a gaseous product, CO₂
KHCO₃ + HBr → KBr + H₂O + CO₂
Molarity is moles of solute per litre of solvent. We're given mass of solute, but can convert to moles using the molar mass of NaOH (40 g/mol). There are 10 g / 40 g/mol = 0.25 mol of NaOH in the solution.
M = 0.25 mol / 2.0 L = 0.125M
The second answer (0.13M) is the correct one.
Explanation:
Elements that belong to same group contains same number of valence electrons. Hence, they tend to show similar chemical properties.
When we move across a period then number of electrons get added to the same shell. As a result, there will be no increase in size of elements.
Also, metals are the elements that belong to group 1, 2 and d-block elements are also known as metals. Metallic character of elements decreases when we move left to right in a periodic table.
As most reactive metals are placed on the left side of periodic table.
Since, size of elements increases on moving down the group. So, an element is able to easily lose its valence electrons because of less force of attraction between its nucleus and valence electrons.
As a result, there will be increase in reactivity of metals on moving down the group.
Thus, we can conclude that given sentences are as follows.
- Elements in the same group have the same number of valence electrons.
-
Elements in the same period have the same number of electron shells.
-
Metallic elements become less reactive as you move left to right in a period.
-
Metallic elements become more reactive as you move top to bottom in a group.
The metal is lead, Pb.
One unit of the oxide contains one atom of O (16.00 u).
∴ Mass of oxide = 16.00 u O × (100 u MO/7.17 u O) = 223.15 u MO
Mass of M = mass of MO – mass of O = 223.15 u -16.00 u = 207.2 u
The only element with an atomic mass of 207.2 u is lead (Pb) and the formula of the oxide is PbO.
Answer:
P1V1= P2V2
Explanation:
Inverse relationship
V2 = V1 X P1/P2
V2= 14.3 L x 45.0 mm Hg/63.0 mmHg= 8.99
