Answer:
Titration
Explanation:
The best technique which can be used to determine the number of moles of the HCl in the sample is titration.
The given amount of HCl solution must be titrated with known concentration of the base like NaOH.
The volume of NaOH required must be noted also.
According to the reaction,

At equivalence point
Moles of
= Moles of 
Considering:-
Moles of 
Thus, in this way, moles of HCl can be determined.
Answer:
2.24dm³
Explanation:
Given parameters:
Mass of He = 40g
Unknown:
Volume of Helium = ?
Solution:
To solve this problem, we convert the given mass to number of moles.
Number of moles =
molar mass of He = 4g/mol
Number of moles =
= 0.1mole
So;
1 mole of gas at rtp occupies a volume of 22.4dm³
0.1 mole of He will occupy a volume of 0.1 x 22.4 = 2.24dm³
Galileo disproved the Ptolemaic theory, sanctioned for centuries by the Church, which held the Earth to be the central and principal object in the universe, about which all celestial objects orbited.
Answer:
The health effects of ozone layer depletion is discussed below
Explanation:
. Ozone layer depletion effects improved UV radiation levels at the
Earth's covering, which is degrading to human well-being.
Negative consequences involve improvements in several varieties of
skin cancers, eye cataracts, and immune insufficiency diseases.
• Ozone layer exhaustion improves the quantity of UVB that touches the
Earth's exterior.
Answer:
physical property
Explanation:
it is physical so is any melting and boiling point