All categories

2 years ago

If 6.5 L of water is added to 4.5 L of a 2.8 M Ca(OH)2 solution, what is the molarity of the new solution?

1 answer:

6 0

Find moles of Ca(OH)2 first:

moles = 2.8 x 4.5 = 12.6

Now,
After addition, new volume = 6.5 + 4.5 = 11.0

So, new molarity = 12.6 / 11 = 1.145

You might be interested in

How do solve for density?

Pachacha [2.7K]

Density(D) is defined as Mass(M) divided by Volume(V).

The formula for Density is:

D = M / V.

Another way to remember the formula for Density is to remember "Mass per unit of volume".

I hope this helps!

7 0

2 years ago

Concentrated hydrogen peroxide solutions are explosively decomposed by traces of transition metal ions (such as Mn or Fe): 2H2O2

zalisa [80]

Answer:

23.0733 L

Explanation:

The mass of hydrogen peroxide present in 125 g of 50% of hydrogen peroxide solution:

$Mass=\frac {50}{100}\times 125\ g$

Mass = 62.5 g

Molar mass of $H_2O_2$ = 34 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus, moles are:

$moles= \frac{62.5\ g}{34\ g/mol}$

$moles= 1.8382\ mol$

Consider the given reaction as:

$2H_2O_2_{(aq)}\rightarrow2H_2O_{(l)}+O_2_{(g)}$

2 moles of hydrogen peroxide decomposes to give 1 mole of oxygen gas.

Also,

1 mole of hydrogen peroxide decomposes to give 1/2 mole of oxygen gas.

So,

1.8382 moles of hydrogen peroxide decomposes to give $\frac {1}{2}\times 1.8382 mole of oxygen gas. Moles of oxygen gas produced = 0.9191 molGiven: Pressure = 746 torr
The conversion of P(torr) to P(atm) is shown below:
[tex]P(torr)=\frac {1}{760}\times P(atm)$

So,

Pressure = 746 / 760 atm = 0.9816 atm

Temperature = 27 °C

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T₁ = (27 + 273.15) K = 300.15 K

Using ideal gas equation as:

PV=nRT

where,

P is the pressure

V is the volume

n is the number of moles

T is the temperature

R is Gas constant having value = 0.0821 L.atm/K.mol

Applying the equation as:

0.9816 atm × V = 0.9191 mol × 0.0821 L.atm/K.mol × 300.15 K

8 0

2 years ago

3. Explain the relationship between power, energy and time.

likoan [24]

There is a very simple relationship between the three. First off, power is the amount of energy used over a certain amount of time. Energy is the capacity of carrying out that power. Lastly, time depends on how much energy you have to exert the work.

Hope this helps :)

7 0

2 years ago

A change in which property of light will have no effect on whether or not the photoelectric effect occurs?

lorasvet [3.4K]

Answer:

intensity

Explanation:

Intensity has no affect on whether or not the photoelectric effect occurs. The determining property is frequency and since frequency and wavelength are inversely proportional, wavelength matters as well

3 0

2 years ago

What is the molecular geometry of PBr3? A. trigonal pyramidal B. trigonal planar C. linear D....

lubasha [3.4K]

The correct answer is:

TRIGONAL PYRAMIDAL

4 0

2 years ago