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2 years ago

6

Which is a chemical change

1 answer:

yuradex [85]2 years ago

4 0

I think it is wood burning :)

hope I helped

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of an unknown protein are dissolved in enough solvent to make 5.00mL of solution. The osmotic pressure of this solution is measu

krok68 [10]

The question is incomplete . The complete question is :

100 mg of an unknown protein are dissolved in enough solvent to make 5.00mL of solution. The osmotic pressure of this solution is measured to be 0.107atm at 25.0°C. Calculate the molar mass of the protein. Round your answer to 3 significant digits.

Answer: The molar mass of the protein is $4.57\times 10^3g/mol$

Explanation:

$\pi =CRT$

$\pi=i\times \frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}\times RT$

where,

$\pi$ = osmotic pressure of the solution = 0.107 atm

i = Van't hoff factor = 1 (for non-electrolytes)

Mass of solute (protein) = 100 mg = 0.1 g (Conversion factor: 1 g = 1000 mg)

Volume of solution = 5.00 mL

R = Gas constant = $0.0821\text{ L.atm }mol^{-1}K^{-1}$

T = temperature of the solution = $25^oC=[273+25]=298K$

Putting values in above equation, we get:

$0.107=1\times \frac{0.1\times 1000}{\text{Molar mass of insulin}\times 5.00}\times 0.0821\text{ Latm }mol^{-1}K^{-1}\times 298K\\\\\text{molar mass of protein}$

$\text{molar mass of protein}=4.57\times 10^3g/mol$

Hence, the molar mass of the protein is $4.57\times 10^3g/mol$

7 0

2 years ago

A substance X contains 10 gram of calcium carbonate calculate the number of mole of calcium carbonate present in X

Tasya [4]

$\LARGE{ \boxed{ \rm{ \red{Required \: answer}}}}$

☃️ Chemical formulae ➝ $\sf{CaCO_3}$

<h3><u>How to find?</u></h3>

For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.

$\boxed{ \sf{No. \: of \: moles = \frac{given \: weight}{molecular \: weight} }}$

<h3><u>Solution:</u></h3>

Atomic weight of elements:

Ca = 40

C = 12

O = 16

❍ Molecular weight of $\sf{CaCO_3}$

= 40 + 12 + 3 × 16

= 52 + 48

= 100 g/mol

❍ Given weight: 10 g

Then, no. of moles,

⇛ No. of moles = 10 g / 100 g mol‐¹

⇛ No. of moles = 0.1 moles

☄ No. of moles of Calcium carbonate in that substance = <u>0.1 moles</u>

<u>━━━━━━━━━━━━━━━━━━━━</u>

3 0

3 years ago

Read 2 more answers

How many total atoms are in 0.680 g of P₂O5?

Ludmilka [50]

Answer: 2.88× $10^{24}$ atoms $P_{2}O_{5}$

Explanation: First, using stoichiometry, we must convert this from grams to moles, then from moles to atoms.

1. For the first step, we should also look at the periodic table to find the molar mass of the compound, then use that as the denominator.

$0.680g P_{2} O_{5} *\frac{1molP_{2} O_{5} }{141.948gP_{2} O_{5} } =4.79mol P_{2} O_{5}$

2. Now that it is converted to moles, we must convert it to atoms by multiplying it by Avogadro's number.

$4.79molP_{2} O_{5} *\frac{6.022X10^{23} }{1mol} =2.88*10^{24}$

With this information, we know that there are $2.88X10^{24}$ total atoms in 0.680 grams $P_{2} O_{5}$ .

I hope this helps! Pls give brainliest!! :)

8 0

1 year ago

A student measures the mass of a sample as 9.64 g. Calculate the percentage error, given that the correct mass is 9.80 g.

rosijanka [135]

Answer:

<h3>The answer is 1.63 %</h3>

Explanation:

The percentage error of a certain measurement can be found by using the formula

$P(\%) = \frac{error}{actual \: \: number} \times 100\% \\$

From the question

actual mass = 9.80 g

error = 9.80 - 9.64 = 0.16

We have

$p(\%) = \frac{0.16}{9.80} \times 100 \\ = 1.632653061...$

We have the final answer as

<h3>1.63 %</h3>

Hope this helps you

5 0

3 years ago

17 POINTS!!! JUST DO A B C D PLS!!!! PLS DONT COMMENT IF YOU DONT KNOW IT ITS DUE BY TOMORROW AND I CANT KEEP WASTING POINTS PLS

dimulka [17.4K]

Answer:

A B C D E

Explanation:

7 0

2 years ago