There are 3 types of atoms in an ammonia solution, NH4OH: nitrogen, hydrogen and oxygen. So, your answer in this context is A.
However, if you were considering just ammonia on its own (NH3) there are only two types of atoms, nitrogen and hydrogen.
Answer:
Mass = 20 g
Explanation:
Given data:
Number of moles of He = 5 mol
Mass of He = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass = 4 g/mol
by putting values,
5 mol = Mass / 4 g/mol
Mass = 5 mol × 4 g/mol
Mass = 20 g
Answer:
weighing balance/analytical balance
Graduated cylinder/buret
Explanation:
The mass of the evaporating basin could be measured using a weighing balance or an analytical balance. Both are classified as weighing scales but the analytical balance can measure the mass of objects up to 4 decimal places, thus, providing better accuracy in measurement than ordinary weighing balance that can only measure up to 2 decimal places.
In order to measure 50 cm3 of the sea water, a graduated cylinder or a buret can be used. Both equipment can measure up to the same decimal places and, thus, have virtually the same accuracy.
Answer:
Putting salt on the ground to melt ice or snow I mean.
Explanation: