All categories

3 years ago

10.How do you make sure there is no cross contamination of your samples of substances?

Chemistry

1 answer:

alexgriva [62]3 years ago

6 0

Have a clean workspace, always wear clean gloves, never reuse or leave Lab wearing gloves, sanitize!

You might be interested in

Determine the [H3O+] in a 0.265 M HClO solution. The Ka of HClO is 2.9 × 10-8.

dexar [7]

8.8 × 10-5 M is the [H3O+] concentration in 0.265 M HClO solution.

Explanation:

HClO is a weak acid and does not completely dissociate in water as ions.

the equation of dissociation can be written and ice table to be formed.

HClO +H2O ⇒ ClO- + H3O+

I 0.265 0 0

C -x +x +x

E 0.265-x +x +x

Now applying the equation of Ka, where Ka is given as 2.9 × 10-8.

Ka = $\frac{[ClO-][H3O+]}{[HClO]}$

2.9 × 10^-8 = $\frac{[x] [x]}{[0.265-x]}$

$x^{2}$ = 7.698 x $10^{-9}$

x = 8.8 × 10-5 M

The hydronium ion concentration is 8.8 × 10-5 M in 0.265 M solution of HClO.

8 0

3 years ago

Calculate the concentration of acetate ion in a buffer solution made from 2.00 mL of 0.50 M acetic acid and 8.00 mL of 0.50 sodi

Lelu [443]

Answer:

1 M

Explanation:

Equation of reaction is;

CH3COOH + CH3COONa -------------------> 2CH3COO^- + NaH

1 moles of each of the reactants react to give 2 moles of the acetate ion.

From the question, we have that 2.00 mL that is (2÷1000)L of 0.50 M acetic acid reacted with 8.00 mL that is (8/1000)L of 0.50 sodium acetate.

Then from equation, n = CV -------------------------------------------(1).

Where n= number of moles, V= volume, C= concentration.

Number of moles,n of acetic acid = 0.50M× 2/1000L.

n(acetic acid)= 0.001 moles.

Number of moles,n of sodium acetate= 0.50M ×(8/1000)L.

n(sodium acetate)= 0.004 moles.

0.001 moles of acetic acid react with 0.004 moles of Sodium acetate

Therefore, acetic acid is the limiting reagent.

One mole of acetic acid produces 2 moles of acetate ion.

0.001 mole of acetic acid produces= 0.002 moles of acetate ion.

Using the equation (1) that is, n= CV.

0.002= C× 2/1000

C= 0.002/0.002

C= 1 M

8 0

3 years ago

Which type of combination is a mixture?

DochEvi [55]

Answer:

C. physical

Explanation:

A mixture is a physical combination. Mixtures are combinations of compounds and molecules without any chemical reaction taking place.

Mixtures have the following properties:

They have an indefinite composition i.e they consist of two or more elements and or compounds in any proportion by mass
Their constituents retains their identities i. e physical property is retained.
Their constituents reacts differently to changed conditions.
They are easily separated into constituents by physical methods

8 0

3 years ago

6. Which example has BOTH ionic and covalent bonds? *

Fed [463]

Answer:

It’s either A or D buttttt probably d

Explanation:

7 0

3 years ago

QUESTION 1 The ____________________ fan switch is nothing more than a thermostat that closes on a rise in temperature to start t

AVprozaik [17]

Answer:

temperature controlled

7 0

3 years ago