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3 years ago

Explain why we must balance all chemical equations

Chemistry

2 answers:

Illusion [34]3 years ago

4 0

Explanation:

the chemical equation needs to be balance so that it follows the law of conservation of mass. a balance chemical equation occurs when the number of the different atoms of elements to the reactants side is equal to that of the product side. balancing chemical equation is a process of trial and error .

enyata [817]3 years ago

3 0

Answer:

The chemical equation needs to be balanced so that it follows the law of conservation of mass.

Explanation:

You might be interested in

9. Using the balanced equation from Question #8, how many grams of lead will be produced if 2.54 grams of PbS is burned with 1.8

MissTica

Answer: 2.24 grams of Pb

Explanation:

Step 1

Balanced chemical reaction;

2PbS + 3O2 → 2Pb + 2SO3

Step 2

Moles of both PbS and O2

Moles = mass / molar mass

Moles of PbS = 2.54 g / 239.3 g/mol = 0.0108 moles

Moles of O2 = 1.88 / 32 g/mol = 0.0588 moles

Step 3

Finding the limiting reactant.

Limiting reactant, is that reactant which is completely used in the reaction;

If we assume that PbS is the limiting reactant;

We have 0.0588 moles of O2. This needs ( 0.0588 * 2) / 3 = 0.0392 moles of PbS to fully react. But we have only 0.0108 moles of PbS available. That means that the PbS will be completely consumed hence the limiting reactant

If we assume O2 is the limiting reactant;

We have 0.0108 moles of PbS. That needs ( 0.0108 * 3) / 2 = 0.0162 moles of O2. But we have 0.0588 moles of O2 which is in excess further confirming that PbS is the limiting reactant since it will be depleted in the reaction.

Step 4

Moles of lead

For this step we apply the mole ratios with the limiting reactant;

Mole ratio of PbS : Pb = 2 : 2 = 1 : 1

Therefore;

Moles of Pb = (0.0108 moles * 1 ) 1

Moles of Pb =0.0108 moles

Step 5

Mass of Pb

Mass = moles * molar mass

Mass of Pb =0.0108 moles * 207.2 g/mol

Mass of Pb = 2.24 grams

5 0

2 years ago

PLSSS HELP FAST

Aliun [14]

Note the formula

$\boxed{\sf Mass\:no=No\:of\:protons+No\:of\:neutrons}$

For X:-

No of protons:-

$\\ \sf\longmapsto 19-10=9protons$

It is Fluorine.

For Y:-

No of protons:-

$\\ \sf\longmapsto 16-8=8protons$

It is Oxygen.

Option D is correct

7 0

2 years ago

Some common substances used in the laboratory are listed in the table. the chemical formulas of the substances are also listed b

Helga [31]

Its 5 i think

but dont take my word on it

7 0

3 years ago

The volume of a gas is 6.10 l, measured at 1.50 atm. what is the pressure of the gas in

Volgvan

Answer:

713.96mmhg

Explanation:

p1v1=p2v2

6.10×1.50/9.74

=0.939atm

=0.939*760

=713.96mmhg

5 0

2 years ago

A current of 5. 68 a is passed through a Fe(NO3)2 solution. How long, in hours, would this current have to be applied to plate o

daser333 [38]

There are 1.2 hr would this current have to be applied to plate out 7. 20 g of iron .

Calculation ,

Given ; Current ( I ) = 5. 68 A

In $Fe(NO_{3} )_{2}$ , the valancy of Fe is +2 .

2 moles of $e^{-}$ are required for the decomposition of 1 mole of Fe .

7. 20 g of Fe in moles = 7. 20 g /55.845 g/mol =0.12 mole

x moles of $e^{-}$ are required for the decomposition of 0.128 mole of Fe .

moles of $e^{-}$ are required = 0.256 moles

Charge on 1 mole of $e^{-}$ = 96500 C

Charge on 0.256 mole of $e^{-}$ = 24704 C

Current ( I )= Q/t

t =Q / I = 24704 C/5. 68 A = 4349 sec = 1.2 hr

Therefore , there are 1.2 hr would this current have to be applied to plate out 7. 20 g of iron .

To learn more about iron

brainly.com/question/18500540

#SPJ4

8 0

1 year ago