Answer:
The advantages of using an indicator to inform pH measurements:
It gives a mathematically result of the pH, in addition, it gives the precise pH of solvent, and it also gives an idea of the straight of the solution also.
Now, the advantage of using a pH meter:
It is a rapid method to characterize between acids, bases. However, this method does not show how strong acid or base actually are, plus it tends to gives a range of acidity or basicity not quite accurate as a result.
Explanation:tr
a) Molar mass of HF = 20 g/mol
Atomic mass of hydrogen = 1 g/mol
Atomic mass of fluorine = 19 g/mol
Percentage of an element in a compound:

Percentage of fluorine:

Percentage of hydrogen:

b) Mass of hydrogen in 50 grams of HF sample.
Moles of HF = 
1 mole of HF has 1 mole of hydrogen atom.
Then 2.5 moles of HF will have:
of hydrogen atom.
Mass of 2.5 moles of hydrogen atom:
1 g/mol × 2.5 mol = 2.5 g
2.5 grams of hydrogen would be present in a 50 g sample of this compound.
c) As we solved in part (a) that HF molecules has 5% of hydrogen by mass.
Then mass of hydrogen in 50 grams of HF compound we will have :
5% of 50 grams of HF = 
Answer:
Choice A: approximately
.
Explanation:
Note that the unit of concentration,
, typically refers to moles per liter (that is:
.)
On the other hand, the volume of the two solutions in this question are apparently given in
, which is the same as
(that is:
.) Convert the unit of volume to liters:
.
.
Calculate the number of moles of
formula units in that
of the
solution:
.
Note that
(sulfuric acid) is a diprotic acid. When one mole of
completely dissolves in water, two moles of
ions will be released.
On the other hand,
(sodium hydroxide) is a monoprotic base. When one mole of
formula units completely dissolve in water, only one mole of
ions will be released.
ions and
ions neutralize each other at a one-to-one ratio. Therefore, when one mole of the diprotic acid
dissolves in water completely, it will take two moles of
to neutralize that two moles of
produced. On the other hand, two moles formula units of the monoprotic base
will be required to produce that two moles of
. Therefore,
and
formula units would neutralize each other at a two-to-one ratio.
.
.
Previous calculations show that
of
was produced. Calculate the number of moles of
formula units required to neutralize that
.
Calculate the concentration of a
solution that contains exactly
of
formula units:
.
A. 1 valence electron
b. 4 valence electrons
c. 2 valence electrons
d. 6 valence electrons
I believe it is d. physical shape n particle amount (amount of particle increase if u gain weight right?), weight directly proportional to mass..