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3 years ago

14

Please I really really need help!!!!

1 answer:

Zigmanuir [339]3 years ago

4 0

Answer:

1) It is the number of particles in one mole of substance. It is an arbitrary definition to denote an amount of substance, not by its weight but by its number of molecules. Why? because that is convenient when doing certain calculations involving molecule formulas.

2) 1 mole of substance contains exactly as many particles as there are atoms in 12 grams of carbon-12.

3) The unified atomic mass unit is 1/12 of the mass of 1 carbon-12 atom.

So you see all three concepts are linked together.

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a chemical company makes pure silver by reacting silver nitrate with Zinc. the company needs to make 800 grams of pure silver fo

shutvik [7]

The reaction between zinc and silver nitrate is

$Zn + 2 AgNO3 \rightarrow Zn(NO3)2 + 2 Ag$

Moles of Zn = m /M = 599 /65 = 9.2 mol

Moles of AgNO3 = m /M = 1500 /169 = 8.87 mol

Silver nitrate is reacting completely to give silver

Thus, moles of Silver nitrate is equivalent to silver = 8.87

For mass of silver produced

m /M = 8.87 = m /107

m = 949.24 g

Hence, the given quantity of reactants are sufficient to produce 800 g of silver as the amount of silver produced is 949.24 g

3 0

4 years ago

A chemist prepares a solution by adding 258 mg of K2Cr2O7 (MW = 294.19 g/mol ) to a volumetric flask, and then adding water unti

Maksim231197 [3]

Answer: Molarity of the prepared solution is $1.75\times 10^{-3}mole/L$

Explanation:

Molarity is defined as the number of moles of solute dissolved per liter of the solution.

$Molarity=\frac{n\times 1000}{V_s}$

where,

n= moles of solute

$V_s$ = volume of solution in ml = 500 ml

moles of solute = $\frac{\text {given mass}}{\text {molar mass}}=\frac{0.258g}{294.19g/mol}=8.77\times 10^{-4}mol$

Now put all the given values in the formula of molarity, we get

$Molarity=\frac{8.77\times 10^{-4}moles\times 1000}{500ml}=1.75\times 10^{-3}mole/L$

Thus molarity of the prepared solution is $1.75\times 10^{-3}mole/L$

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3 years ago

There are three types<br> of atoms, which on gains and looses electrons?

Stells [14]

Answer:

https://courses.lumenlearning.com/boundless-biology/chapter/atoms-isotopes-ions-and-molecules/

Explanation:

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3 years ago

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saw5 [17]

Answer:

2

Explanation:

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3 years ago

Which statement best describes the liquid state of matter?

Andrei [34K]

Answer:

There are no acceptable descriptions at all on that list of choices.

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4 years ago

Read 2 more answers