All categories

3 years ago

Am I doing this right? What is [OH-] of a solution with a pH of 4.0? Answer in M

Chemistry

1 answer:

jok3333 [9.3K]3 years ago

4 0

Am I doing this right?

What is [OH-] of a solution
with a pH of 4.0?

Answer in M
Ya

You might be interested in

A bar of pure gold is made up of identical gold atom. can it be a molecular compound?

Zepler [3.9K]

No it can't. To be a molecular compound it should contains at least two different elements. As it is made up of only gold (Au) atoms it violates the above requirement.

6 0

3 years ago

7. Which of the following would lower the pitch of a string instrument's sound?

vfiekz [6]

The correct option is C.

The pitch of a string refers to the quality of sound that is produced by the string when it vibrates. There are three basic factors that affect the quality of pitch of a string, these are: the tension, the thickness of the string and the length of the string. The higher the thickness of the string, the lower the pitch of the string, thus, increasing the thickness of the string will lower the pitch.

3 0

3 years ago

Read 2 more answers

Which gas sample STP has the same total number of molecules at 2.0 L of CO2(g) at STP

zloy xaker [14]

Answer 2 (2.0L of Cl2 (g)) is correct. Avogadro's hypothesis states that 2.0 L of Cl2 (g) occupies the same volume as 2.0 L of CO2

8 0

3 years ago

Gallium is produced by the electrolysis of a solution obtained by dissolving gallium oxide in concentrated NaOH(aq). Calculate t

Alina [70]

Answer: The mass of gallium produced by the electrolysis is 0.0354 grams.

Explanation:

The equation for the deposition of Ga(s) from Ga(III) solution follows:

$Ga^{3+}(aq.)+3e^-\rightarrow Ga(s)$

To calculate the total charge, we use the equation:

$C=I\times t$

where,

C = charge

I = current = 0.490 A

t = time required (in seconds) = $50\times 60=300s$ (Conversion factor: 1 min = 60 s)

Putting values in above equation, we get:

$C=0.490\times 300=147C$

To calculate the moles of electrons, we use the equation:

$\text{Moles of electrons}=\frac{C}{F}$

where,

C = charge = 147 C

F = Faradays constant = 96500

$\text{Moles of electrons}=\frac{147}{96500}=1.52\times 10^{-3}mol$

Now, to calculate the moles of gallium, we use the equation:

$\text{Moles of Gallium}=\frac{\text{Moles of electrons}}{n}$

where,

n = number of electrons transferred = 3

Putting values in above equation, we get:

$\text{Moles of Gallium}=\frac{1.52\times 10^{-3}}{3}=5.077\times 10^{-4}mol$

To calculate the mass of gallium, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Moles of Gallium = $5.077\times 10^{-4}mol$

Molar mass of Gallium = 69.72 g/mol

Putting values in above equation, we get:

$5.077\times 10^{-4}mol=\frac{\text{Mass of Gallium}}{69.72g/mol}\\\\\text{Mass of Gallium}=0.0354g$

Hence, the mass of gallium produced by the electrolysis is 0.0354 grams.

8 0

3 years ago

How much heat energy is produced by 0.5 Wh of electrical energy

n200080 [17]

1 W is equivalent to 1 J/s

So,
0.5 Wh = 0.5 (J/s) (h)

Converting h to s,
0.5 (J/s) (h) (60min/1h) (60s/1min) = 1800J

Thefore,
0.5Wh is 1800J or 1.8kJ of heat energy

6 0

4 years ago