Answer:
a. 0.4539g benozic acid
b. 60.29% of benzoic acid in the solid sample
Explanation:
The benzoic acid reacts with NaOH as follows:
C6H5COOH + NaOH → C6H5COONa + H2O
Where 1 mole of the acid reacts per mole of NaOH
The NaCl doesn't react with NaOH
To solve this question we must find the moles of NaOH added = Moles of benzoic acid. With the moles of the acid and its molar mass (C6H5COOH = 122.12g/mol) we can find the mass of the acid and its mass percentage:
a. Moles NaOH = Moles Benzoic acid:
24.78mL = 0.02478L * (0.150mol / L) = 0.003717 moles Benozic acid
Mass benzoic acid:
0.003717 moles Benozic acid * (122.12g / mol) = 0.4539g benozic acid
b. Mass percentage is:
0.4539g / 0.7529g * 100 = 60.29% of benzoic acid in the solid sample
what is the pH of a 2.58 x 10^-6 M solution of an acid?
Answer:
5.59Explanation:
The pH of a solution can be found by using the formula
[tex]pH = - log [ {H}^{+} ][/tex]
From the question we have
[tex]ph = - log(2.58 \times {10}^{ - 6} ) \\ = 5.58838[/tex]
We have the final answer as
5.59Hope this helps you
Which represents a balanced chemical equation?
Answer:
C
Explanation:
Reactant part has 2 Mg and 2 O, product part has 2 Mg and 2 O
THIS NOT MY WORK. its for my sister. HELP HER
Answer:
Your answer will be b(molten material from the outer core makes its way to the surface of earth)
Explanation:
Answer:
C
Explanation:
I'm pretty sure molten material comes from the inner core. I think you can search up this though, try to find where molten material comes from. Goodluck!
Which of the following density formulas have been rearranged correctly? pls help i have no idea what i’m doing
1. v = m/d
2. m = d/v
3. v = md
4. m = v/d
Answer:
v = m/d
Explanation:
To know which option is correct, we shall rearrange the the formula of density. This can be obtained as follow:
The density of a substance is defined as the mass per unit volume of the substance. Mathematically, it is expressed as:
Density (d) = mass (m) / volume (v)
d = m/v
Make m the subject
d = m/v
Cross multiply
m = dv
Next, made v the subject
d = m/v
Cross multiply
dv = m
Divide both side by d
v = m/d
SUMMARY:
From the density formula (i.e d = m/v) we obtained:
m = dv
v = m/d
Therefore, option v = m/d gives the correct answer to the question.
A toy helicopter takes off and moves 2 m up and then 2 m back down. What
is the displacement of the helicopter?
A. 0 m
B. 2 m down
C. 2 m up
D. 4 m
Answer:
0m
Explanation:
2m up - 2m down =0m
Determine the spec gravity of 500 mL alcohol if the density is 0.79g/ml
Answer:
S.G = 0.79.
Explanation:
Hello there!
In this case, according to the given information in the problem, it turns out possible for us to calculate the specific gravity of this alcohol by simply dividing its density, 0.79 g/mL by that of the water, 1 g/mL just as a reference for us to work with:
[tex]S.G=\frac{\rho _{alc}}{\rho _w}[/tex]
Thus, we plug in the densities to obtain:
[tex]S.G=\frac{0.79g/mL}{1g/mL}\\\\S.G=0.79[/tex]
Which is dimensionless as g/mL is cancelled out due to its presence on both top and bottom of the previous formula.
Regards!