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antiseptic1488 [7]
3 years ago
14

Determine the percent composition of potassium dichromate, K2Cr2O7.

Chemistry
1 answer:
bulgar [2K]3 years ago
4 0

Answer:

Option E is the correct one

Explanation:

K₂Cr₂O₇ → Potassium dichromate

A ionic salt which its molar mass is 294.18 g/m

It is composed by 2 mol of K, 2 mol of Cr and 7 mol of O

2 mol of K = 78.2 g

2 mol of Cr = 104 g

7 mol of O = 112 g

In 294.2 g of compound we have __78.2 g K __ 104 g Cr ___ 112 g O

Let's calculate the percent

(78.2 / 294.2) .100 = 26.59% K

(104 / 294.2) .100 = 35.35% Cr

(112 / 294.2) . 100 = 38.06 % O

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HELP PLEASE THE OTHER 'ANSWER' ISNT EVEN AN ANSWER!
hodyreva [135]

Answer:

most likely that (2) the replicated experiment was performed incorrectly.

Why, u ask? u dare question me:

1- The initial experiment invalidness cannot be proven.

2- <em><u>t</u></em><em><u>h</u></em><em><u>e</u></em><em><u> </u></em><em><u>s</u></em><em><u>e</u></em><em><u>c</u></em><em><u>o</u></em><em><u>n</u></em><em><u>d</u></em><em><u> </u></em><em><u>a</u></em><em><u>n</u></em><em><u>s</u></em><em><u>w</u></em><em><u>e</u></em><em><u>r</u></em><em><u> </u></em><em><u>i</u></em><em><u>s</u></em><em><u> </u></em><em><u>c</u></em><em><u>o</u></em><em><u>r</u></em><em><u>r</u></em><em><u>e</u></em><em><u>c</u></em><em><u>t</u></em>

3- Different labaratories does not effect the outcome, as long as the parameter and environment of the replicated experiment is the same as when the initial experiment was conducted.

4- Already knowing the data and errors would increase the precision of the replicated experiment.

5- Change in variables should still be in the objective (or purpose) of the experiment, thus, major difference in the outcome should not happen.

happy learning!

4 0
3 years ago
4. This is the idea that energy can be transformed from one form to another, but it
nordsb [41]

Answer:

Law of Conservation of Energy

Explanation:

6 0
3 years ago
What is the density of a liquid that has a mass of 27g and a volume of 30mL?
NNADVOKAT [17]
  • Answer: 7 g/cm to the third power
  • Hope this helps
  • Please mark brainliest
  • Have a nice day
  • stay safe

-Carrie

8 0
3 years ago
What is the energy of a microwave photon that has a frequency of 9.86 x 1012 Hz?
BlackZzzverrR [31]

Answer:

6.533 × 10^-21J

Explanation:

The energy of the microwave photon can be calculated using:

E = hf

Where;

E = energy of photon (J)

h = Planck's constant (6.626 × 10^-34 J/s)

f = frequency (9.86 x 10^12 Hz)

Hence, E = hf

E = 6.626 × 10^-34 × 9.86 x 10^12

E = 65.33 × 10^(-34 + 12)

E = 65.33 × 10^(-22)

E = 6.533 × 10^-21J

The energy of the microwave photon is

6.533 × 10^-21J

5 0
3 years ago
Which statement describes a property that is unique to metalloids?
hodyreva [135]

Answer:

Metalloids are semiconductive.

Explanation:

8 0
3 years ago
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