All categories

3 years ago

What is the percent cr, by mass, in the steel sample? express your answer numerically as a percentage?

2 answers:

8 0

Given:3.40g sample of the steel used to produce 250.0 mLSolution containing Cr2O72−

Assuming all the Cr is contained in the BaCrO4 at the end.
(0.145 g BaCrO4) / (253.3216 g BaCrO4/mol) x (250.0 mL / 10.0 mL) x (1 mol Cr / 1 mol BaCrO4) x (51.99616 g Cr/mol / (3.40 g) = 0.219 = 21.9% Cr

lbvjy [14]3 years ago

3 0

3.40g example of the steel used to deliver 250.0 mL Solution containing Cr2O72−

Expecting all the Cr is contained in the BaCrO4 toward the end.

(0.145 g BaCrO4)/(253.3216 g BaCrO4/mol) x (250.0 mL/10.0 mL) x (1 mol Cr/1 mol BaCrO4) x (51.99616 g Cr/mol/(3.40 g)

= 0.219 = 21.9% Cr

Further Explanation:

Chromium (cr):

Chromium is a compound component with the image Cr and nuclear number 24. It is the primary component in gathering 6. It is a steely-dim, radiant, hard and weak progress metal. Chromium is the principle added substance in tempered steel, to which it includes hostile to destructive properties.

Characterization of chromium:

Classification: Chromium is a progress metal

Color: silver-dark

Nuclear weight: 51.996

State: solid

Softening point: 1907 oC, 2180 K

synthetic properties of chromium:

Chromium is a radiant, fragile, hard metal. Its shading is silver-dark and it tends to be profoundly cleaned. It doesn't discolor in air, when warmed it borns and structures the green chromic oxide. Chromium is unsteady in oxygen, it quickly creates a meager oxide layer that is impermeable to oxygen and secures the metal underneath.

Subject: chemistry

Level: High School

Keywords: Chromium (cr), Characterization of chromium, synthetic properties of chromium.

Related links:

Learn more about evolution on

brainly.com/question/5325748

brainly.com/question/7035326

You might be interested in

The table shows the properties of some organic compounds.

riadik2000 [5.3K]

Yo sup??

since A has a hydroxyl group ie OH therefore it's an alcohol

and since B has an oxygen between two carbons therefore it's an ether.

hence the correct answer is option B

A is alcohol and B is ether

Hope this helps

8 0

3 years ago

In 1860, Chemists could make which of the following statements about the known chemical elements?

LenKa [72]

Answer:

b. Some had similar properties

3 0

3 years ago

When the concentration of A in the reaction A ..... B was changed from 1.20 M to 0.60 M, the half-life increased from 2.0 min to

Reika [66]

Answer:

$0.4167\ \text{M}^{-1}\text{min}^{-1}$

Explanation:

Half-life

${t_{1/2}}A=2\ \text{min}$

${t_{1/2}}B=4\ \text{min}$

Concentration

${[A]_0}_A=1.2\ \text{M}$

${[A]_0}_B=0.6\ \text{M}$

We have the relation

$t_{1/2}\propto \dfrac{1}{[A]_0^{n-1}}$

$\dfrac{{t_{1/2}}_A}{{t_{1/2}}_B}=\left(\dfrac{{[A]_0}_B}{{[A]_0}_A}\right)^{n-1}\\\Rightarrow \dfrac{2}{4}=\left(\dfrac{0.6}{1.2}\right)^{n-1}\\\Rightarrow \dfrac{1}{2}=\left(\dfrac{1}{2}\right)^{n-1}$

Comparing the exponents we get

$1=n-1\\\Rightarrow n=2$

The order of the reaction is 2.

$t_{1/2}=\dfrac{1}{k[A]_0^{n-1}}\\\Rightarrow k=\dfrac{1}{t_{1/2}[A]_0^{n-1}}\\\Rightarrow k=\dfrac{1}{2\times 1.2^{2-1}}\\\Rightarrow k=0.4167\ \text{M}^{-1}\text{min}^{-1}$

The rate constant is $0.4167\ \text{M}^{-1}\text{min}^{-1}$

3 0

2 years ago

What is 1 item that is a compound?<br><br>Give an example of how the 1 item is a compound :D

spayn [35]

Water

Water is a compound because it is made from more than one kind of element (oxygen and hydrogen).

3 0

3 years ago

How do I complete this column graph of the number of conductors vs the number of insulators

Vikentia [17]

Answer:

sorry but i am doing this for point

Explanation:

how do I complete this column graph of the number of conduct vs the number of

4 0

3 years ago