PLEASE ANSWER ASAP please get it right

What is the [H+] of a solution with a pH of 9.40?

LiRa [457]

Answer:

a) 3.98 x 10^-10

Explanation:

Hello,

In this case, for the given pH, we can compute the concentration of hydronium by using the following formula:

$pH=-log([H^+])$

Hence, solving for the concentration of hydronium:

$[H^+]=10^{-pH}=10^{-9.40}\\$

$[H^+]=3.98x10^{-10}M$

Therefore, answer is a) 3.98 x 10^-10

Best regards.

4 0

3 years ago

What reactions are involved in making plastic bags and what are the molecules that make up a plastic bag like?

denpristay [2]

Plastic bags are made up of plastic film, non-woven fabric, or plastic textile. The molecules that are present in plastic bags are polymers. Polymers are large molecules made up of repeating units called monomers.
I know this isn't much, but I hope it helps! :)

8 0

3 years ago

What chemical change is magnetizing steel

labwork [276]

Magnetizing steel is a physical change, not a chemical change.

4 0

3 years ago

The heat of fusion AH, of ethyl acetate (C4H802) is 10.5 kinol. Calculate the change in entropy as when 398. g of ethy, acetate

Hitman42 [59]

Answer: The entropy change of the ethyl acetate is 133. J/K

Explanation:

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

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

Given mass of ethyl acetate = 398 g

Molar mass of ethyl acetate = 88.11 g/mol

Putting values in above equation, we get:

$\text{Moles of ethyl acetate}=\frac{398g}{88.11g/mol}=4.52mol$

To calculate the entropy change for different phase at same temperature, we use the equation:

$\Delta S=n\times \frac{\Delta H_{fusion}}{T}$

where,

$\Delta S$ = Entropy change = ?

n = moles of ethyl acetate = 4.52 moles

$\Delta H_{fusion}$ = enthalpy of fusion = 10.5 kJ/mol = 10500 J/mol (Conversion factor: 1 kJ = 1000 J)

T = temperature of the system = $84.0^oC=[84+273]K=357K$

Putting values in above equation, we get:

$\Delta S=\frac{4.52mol\times 10500J/mol}{357K}\\\\\Delta S=132.9J/K$

Hence, the entropy change of the ethyl acetate is 133. J/K

7 0

3 years ago

This diagram shows the forces acting on a car. The center dot represents the car, and the arrows represent the forces acting on

Mariulka [41]

Answer : The correct option is B- Towards the left.

Solution : Given,

Force on car in upward direction, $F_1$ = 6000 N

Force on car in downward direction, $F_2$ = 6000 N

Force on car in right direction, $F_3$ = 5000 N

Force on car in left direction, $F_4$ = 6000 N

Force : Force is equal to the mass multiplied by the acceleration. The force is directly proportional to the acceleration.

Formula : F = m × a

where, F is force, m is mass and a is acceleration.

From the given diagram we conclude that the $F_1$ and $F_2$ are in opposite direction and the force acting on car are same. So, their net force is zero.

And in case of $F_3$ and $F_4$ , the net force will not be zero because force acting on car are different. The car will accelerate towards left direction because $F_4$ is higher than the $F_3$ .

So, the car will accelerate towards left direction.

3 0

3 years ago