All categories

4 years ago

Perform the following calculations and give your answer with the correct number of significant figures:

1 answer:

3 0

When multiplying numbers, the term with the least significant digits gives how many significant digits will be in the answer. 2.995 has the least with 4 "sig figs", so the answer will have 4 significant digits as well:

2.995/0.16685 = <span>17.9502547198
</span> ↑↑ ↑<span>↑
4 sig figs

So the answer is 17.95.</span>

You might be interested in

3 Cu + SHNO3 — 3 Cu(NO3)2 + 2 NO + 4 H20

LenaWriter [7]

Considering the reaction stoichiometry, the mass of H₂O that is produced when 11.9 moles of HNO₃ react is 107.1 grams.

<h3>Reaction stoichiometry</h3>

The balanced reaction is:

3 Cu + 8 HNO₃ → 3 Cu(NO₃)₂ + 2 NO + 4 H₂O

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

Cu: 3 moles
HNO₃: 8 moles
Cu(NO₃)₂: 3 moles
NO: 2 moles
H₂O: 4 moles

The molar mass of the compounds present in the reaction is:

Cu: 63.54 g/mole
HNO₃: 63 g/mole
Cu(NO₃)₂: 187.54 g/mole
NO: 30 g/mole
H₂O: 18 g/mole

Then, by reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of mass of each compound participate in the reaction:

Cu: 3 moles ×63.54 g/mole= 190.62 grams

HNO₃: 8 moles ×63 g/mole= 504 grams

Cu(NO₃)₂: 3 moles ×187.54 g/mole= 562.62 grams

NO: 2 moles ×30 g/mole= 60 grams

H₂O: 4 moles ×18 g/mole= 72 grams

<h3>Mass of H₂O produced</h3>

It is possible to determine the the amount of mass of H₂O produced by a rule of three: if by stoichiometry 8 moles of HNO₃ produce 72 grams of H₂O, if 11.9 moles of HNO₃ react how much mass of H₂O will be formed?

$mass of H_{2}O=\frac{11.9 moles of HNO_{3} x72 grams of H_{2}O}{8 moles of HNO_{3}}$

<u><em>mass of H₂O= 107.1 grams</em></u>

In summary, the mass of H₂O that is produced when 11.9 moles of HNO₃ react is 107.1 grams.

Learn more about reaction stoichiometry:

brainly.com/question/11999193

brainly.com/question/15111313?referrer=searchResults

brainly.com/question/9926203?referrer=searchResults

brainly.com/question/6061451?referrer=searchResults

3 0

2 years ago

Diagram how a solids molecular structure is different from a liquids molecular structure

ratelena [41]

Pretty much, for solids draw the molecules close together and rigid, for liquids, the molecules are spaced apart a little and not all lined up

7 0

3 years ago

Explain The element lithium has two common isotopes: Li–6 and Li–7 If the average atomic mass of lithium is 6.94004 u, determine

rosijanka [135]

Answer:

%Li-6 = 5.996% & %Li-7 = 94.004%

Explanation:

let X₁ = Li-6 & X₂ = Li-7 where Xₙ = mole fraction

X₁ + X₂ = 1 => X₁ = 1 - X₂

6·X₁ + 7·X₂ = 6.94004

=> 6(1 - X₂) + 7·X₂ = 6.94004

=> 6 - 6·X₂ + 7·X₂ = 6.94004

=> 6 + X₂ = 6.94004

X₂ = 6.94004 - 6 = 0.94004 => %X₂ = %Li-7 = 94.004%

X₁ = 1.00000 - 0.94004 = 0.05996 => %X₁ = %Li-6 = 5.996%

6 0

3 years ago

Show the empirical formula manganese fluoride; 59.1% Mn and 40.9% F. Fill in the subscripts on the formula below. Make sure to h

Gre4nikov [31]

Hey there!:

Given % of Mn=59.1% means 59.1 g of Mn present in 100 g of manganese fluoride.

Molar mass of Mn= 54.938 g/mol

Moles of Mn = mass / molar mass

59.1 /54.938 => 1.07 ≈ 1 mol.

and % of F=40.9% means 40.9 g of of F present in 100 g of manganese fluoride.

Molar mass of F=18.998 g/mol

Moles of F :

40.9 / 18.999 => 2.15 mol ≈ 2 mol.

The mole ratio between Mn:F= 1 : 2

Therefore the empirical formula of manganese fluoride:

=> MnF2=Mn1F2

Hope that helps!

3 0

4 years ago

Read 2 more answers

Calculate the volume of one mole of a gas at 1.00 atm pressure and 0 °C.

N76 [4]

Answer:

Solution:-

The gas is in the standard temperature and pressure condition i.e. at S.T.P

Therefore,

=22.4dm

As given that the expansion is isothermal and reversible

∴ΔU=0

Now from first law of thermodynamics,

ΔU=q+w

∵ΔU=0

∴q=–w

Given that the heat is absorbed.

∴q=1000cal

⇒w=−q=−1000cal

Now,

Work done in a reversible isothermal expansion is given by-

w=−nRTln(

)

Given:-

T=0℃=273K

n=1 mol

∴1000=−nRTln(

)

⇒1000=−1×2.303×2×273×log(

22.4

)

Explanation:

6 0

3 years ago