How many moles of Cl– ions are in 2.20 L of 1.50 M of sodium-chloride aqueous solution?

Tris is a molecule that can be used to prepare buffers for biochemical experiments. It exists in two forms: Tris (a base) and Tr

ale4655 [162]

Solution :

For the reaction :

$\text{TrisH}^+ + H_2O \rightarrow \text{Trish}^- + H_3O^+$

we have

$Ka = \frac{[\text{Tris}^- \times H_3O]}{\text{Tris}^+}$

$=\frac{x^2}{0.02 -x}$

$=8.32 \times 10^{-9}$

Clearing $x$ , we have $x = 1.29 \times 10^{-5} \text{ moles of acid}$

So to reach $\text{pH} = 7.8 (\text{pOH}= 14-7.8=6.2)$ , one must have the $\text{OH}^-$ concentration of the :

$\text{[OH}^-]=10^{-pOH} = 6.31 \times 10^{-7} \text{ moles of base}$

So we can add enough of 1 M NaOH in order to neutralize the acid that is calculated above and also adding the calculated base.

$\text {n NaOH}=1.29 \times 10^{-5}+6.31 \times 10^{-7}$

$= 1.35 \times 10^{-5} \text{ moles}$

Volume NaOH $= 1.35 \times 10^{-5} \text{ moles} \times \frac{1000 \text{ mL}}{1 \text{ mol}} = 0.0135 \text{ mL}$

Tris mass $H^+ = 0.02 \text{ mol} \times 157.6 \text{ g/mol}=3.152 \text{ g}$

Now to prepare the said solution we must mix:

$3.152 \text{ g Tris H} + 0.0135 \text{ mL NaOH} \ 1 M$ gauge to 1000 mL with water.

3 0

3 years ago

Which of the following can serve as evidence to support the claim that human consumption of water impacts earths system

Brilliant_brown [7]

Ouestion: Which of the following can serve as evidence to support the claim that human consumption of water impacts earths system?

Answer & Explanation: Typically as human populations and per-capita consumption of natural resources increase, so do the negative impacts on Earth unless the activities and technologies involved are engineered otherwise. (MS-ESS3-3), (MS-ESS3-4)

Hope this helps and comment down below if you need more information!

Fr0ggyLikeSMELLY

7 0

3 years ago

A compound has the empirical formula . a 256-ml flask, at 373 k and 750. torr, contains 0.527 g of the gaseous compound. give th

CaHeK987 [17]

<span>Answer: From the ideal gas law, MM=mRTPV; where MM = molecular mass; m = mass; P = pressure in atmospheres; V= volume in litres; R = gas constant with appropriate units. So, 0.800â‹…gĂ—0.0821â‹…Lâ‹…atmâ‹…Kâ’1â‹…molâ’1Ă—373â‹…K0.256â‹…LĂ—0.987â‹…atm = 97.0 gâ‹…molâ’1. nĂ—(12.01+1.01+2Ă—35.45)â‹…gâ‹…molâ’1 = 97.0â‹…gâ‹…molâ’1. Clearly, n = 1. And molecular formula = C2H2Cl2. I seem to recall (but can't be bothered to look up) that vinylidene chloride, H2C=C(Cl)2 is a low boiling point gas, whereas the 1,2 dichloro species is a volatile liquid. At any rate we have supplied the molecular formula as required.</span>

4 0

4 years ago

Differentiate between elements and mixtures

Ksenya-84 [330]

Answer:

ELEMENTS MIXTURE

Elements are made up of one kind of atoms. Mixtures are made up of two or more kinds of Compounds .

Elements cannot be broken down into simpler substances by any physical or chemical method. The various constituents are seperated by simple physical means

3 0

2 years ago

Read 2 more answers

Calculate the number of grams of Hydrogen required to produce 5.73 grams of water. 2H2+O2--->2H2O 2 grams 0.636 grams 1.2 gra

rusak2 [61]

Explanation:

32

2H

2

+O

2

→2H

2

O

Molecular mass of H

2

=2 g/mol

Molecular mass of O

2

=32 g/mol

From the balanced chemical equation,

2×2=4 g of hydrogen requires 32 g of Oxygen to react completely

3 0

3 years ago