Answer:
Explanation:
Molarity is a measure of concentration in moles per liter.
The molarity of the solution is 1.2 M NaNO₃ or 1.2 moles NaNO₃ per liter. There are 0.25 liters of the solution. The moles of solute are unknown, so we can use x.
- molarity= 1.2 mol NaNO₃/L
- liters of solution=0.25 L
- moles of solute =x
We are solving for x, so we must isolate the variable, x. It is being divided by 0.25 liters. The inverse of division is multiplication, so we multiply both sides by 0.25 L.
The units of liters cancel, so we are left with the units moles of sodium nitrate.
There are 0.3 moles of sodium nitrate.
Answer:
Periods on the periodic table of elements
Explanation:
In the periodic table of elements, there are seven horizontal rows of elements called periods. The vertical columns of elements are called groups, or families. (See also The Periodic Table: Metals, Nonmetals, and Metalloids.) In each period (horizontal row), the atomic numbers increase from left to right.
We have to calculate formula mass of N₂O.
The answer is: 44
Relative formula mass is the sum of relative atomic mass of constituent atoms in a formula unit of any compound. Relative formula mass is represented as same symbol of relative molecular mass.
To calculate relative formula mass we need to know number of each atom in the formula and then adding atomic masses of all the atoms.
In N₂O, number of N-atom present is equal to 2 and number of O-atom is equal to 1.
Atomic mass of N-atom is 14 and atomic mass of O-atom is 16.
So, formula mass of N₂O is (2 X 14)+16 = 44.
