<img src="https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B5%7D%20%2B%20%20%5Cfrac%7B2%7D%7B5%7D%20" id="TexFormula1" title=" \frac{1

All categories

Strike441 [17]

3 years ago

}{5} + \frac{2}{5} " alt=" \frac{1}{5} + \frac{2}{5} " align="absmiddle" class="latex-formula">
in simplest form

Chemistry

1 answer:

Travka [436]3 years ago

8 0

3/4 cause its addition

You might be interested in

The atmospheric gases in the thermosphere are heated _____. Pick the best one.

lozanna [386]

by radiation from the Earth's surface

4 0

3 years ago

Read 2 more answers

I have 345mL of a 1.5M NaCl solution. If I boil the water until the volume of the solution is 250mL, what will the molarity of t

Karo-lina-s [1.5K]

Answer is
C. 2.07 M

For explanation

M1V1 = M2V2

M2 = (M1V1)/V2

M2 = (1.5M x 345ml) / 250 ml

:. M2 = 2.07 M

8 0

3 years ago

A buffer solution contains 0.479 M NaHCO3 and 0.342 M Na2CO3. Determine the pH change when 0.091 mol HNO3 is added to 1.00 L of

pshichka [43]

Answer:

ΔpH = 0.20

Explanation:

The buffer of HCO₃⁻ + CO₃²⁻ has a pka of 10.2

HCO₃⁻ ⇄ H⁺ + CO₃²⁻

There are 0.479moles of NaHCO₃ and 0.342moles of Na₂CO₃.

Using Henderson-Hasselbalch formula:

pH = pka + log [Base] / [Acid]

pH = 10.2 + log 0.342mol / 0.479mol

pH = 10.05

NaOH reacts with HCO₃⁻ producing CO₃²⁻, thus:

NaOH + HCO₃⁻ → CO₃²⁻ + H₂O + Na⁺

0.091 moles of NaOH produce the same moles of CO₃²⁻ and consume HCO₃⁻. Moles of these species are:

CO₃²⁻: 0.342mol + 0.091mol: 0.433mol

HCO₃⁻: 0.479mol - 0.091 mol: 0.388mol

Using Henderson-Hasselbalch formula:

pH = pka + log [Base] / [Acid]

pH = 10.2 + log 0.433mol / 0.388mol

pH = 10.25

That means change of pH, ΔpH is:

ΔpH = 10.25 - 10.05 = 0.20

I hope it helps!

3 0

3 years ago

indicate whether the entropy of the system increases or decreases. Mixing 10 mL of 90.0 °C water with 10 mL of 10 °C water. The

Ivanshal [37]

Answer:

When the water is mixed with water at lower temperature the effective temperature of the system (i.e the water at lower temperature) will increase, thereby increasing it's entropy

Explanation:

The answer that "the entropy will is increases" is correct as:

The water at 90° C i.e at higher temperature is mixed with the water at 10° C i.e the water at the lower temperature.

The water at lower temperature will have molecules with lower energy while the water with higher temperature will have molecules undergoing high thermal collisions. Thereby, when the water is mixed with water at lower temperature the effective temperature of the system (i.e the water at lower temperature) will increase, thereby increasing it's entropy.

Therefore, the answer is correct with respect to the water at lower temperature.

Meanwhile, for the water at higher temperature , the temperature of the system will decrease. Thus, the entropy of the water at higher level will decrease.

5 0

4 years ago

If this is a p1000 micropipette, then this is set to dispense [ Select]ul. If this is a p10

mariarad [96]

Answer:

1000 µL; 10 µL

Explanation:

A p1000 micropipet is set to dispense 1000 µL.

A p10 micropipet set to dispense 10 µL.

3 0

3 years ago