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Which expression correctly represents a balanced reduction half-reaction?

jolli1 [7]

For answering for the question, there exists four choices:
1) Na+ + e- -------------- Na
2) Na --------Na+ + e-
3) Cl2 + 2e- ------------ Cl-
4) 2Cl- ---------Cl2 + 2e-

reduction half-reaction general formula is
oxidant + e - or + -------- Product

so in our case the answer is
1) Na+ + e- -------------- Na (exactly balanced)

6 0

4 years ago

Please somebody give me the answers

RSB [31]

Answer:

1. 9.4 grams of methane produce 25.85 grams of CO2

2.Grams of water produced = 11.81 grams

3.Mass of Methane produced by 10.1 gram of O2 = 2.52 grams

4.Amount of methane consumed = 46.9 grams

5. Grams of Co2 produced = 8.32 grams

Explanation:

Molar masses :

Methane = CH4 = mass of C + 4x (mass of H)

CH4 = 12 +4(1) = 16 grams

1 mole of CH4 = 16 gram

Oxygen O2 = 2 x (mass of O) = 2x(16) = 32 gram (1 mole of O2 =32 gram)

Carbon Dioxide =CO2 = mass of C + 2(mass of O)

= 12 + 2(16)

= 44 grams (1 mole of CO2 = 44 gram )

Water = H2O = 18 grams ( 1 mole of H2O = 18 gram)

1 mole of each molecule is equal to their molar masses

The balanced equation is :

$1CH_{4}(g)+2O_{2}\rightarrow 1CO_{2}+2H_{2}O(l)$

According to Stoichiometry :

1 mole of CH4 = 2 Mole of O2 = 1 mole of CO2 = 2 mole of H2O

1. From the equation ,

1 mole of methane produce =1 mole of CO2

16 gram of methane = 44 gram of CO2

1 gram of methane =

$\frac{44}{16}$ gram of CO2

9.4 gram of CH4 =

$\frac{44}{16}\times 9.4$ gram of CO2

= 25 .85 gram of CO2

2.

2 mole of O2 produces = 2 mole of H2O(water)

1 mole of O2 produces = 1 mole of H2O

32 gram of O2 = 18 gram of water

1 gram of O2 =

$\frac{18}{32}$

21 gram of O2 =

$\frac{18}{32}\times 21$

11.81 gram of water

3. 1 mole of CH4 = 2 mole of O2

16 gram of CH4 = 2(32) = 64 grams of O2

64 gram of O2 needs = 16 grams of CH4

1 gram of O2 needs =

$\frac{16}{64}$

10.1 gram of O =

$\frac{16}{64}\times 10.1$ of CH4

= 2.52 gram

4.

1 mole of CO2 is produced from = 1 mole of CH4

44 gram of CO2 is produced from 16 gram of CH4

1 gram CO2 =

$\frac{16}{44}$ gram of CH4

129 gram of CO2 =

$\frac{16}{44}\times 129$ gram of CH4

= 46.90 grams

5.

2 mole of O2 produce = 1 mole of CO2

2x 32 gram of O2 = 44 gram of CO2

1 gram of O2 =

$\frac{44}{64}$ of CO2

12.1 gram of O2 produce=

$\frac{44}{64}\times 12.1$ of CO2

= 8.318 gram

Note : Write the quantity give on left side of "="

write the substance asked on right side of "="

8 0

3 years ago

Help me fill in the blanks

Studentka2010 [4]

First blank -Same
Second blank-Neutral

5 0

4 years ago

How many electrons occupy a filled 7s sublevel

Natali5045456 [20]

Answer:f has 14 electrons in 7 sublevel orbitals,d has 10 electrons in 5 sublevel orbitals,p has 6 electrons in 3 sublevel orbitals,s has 2 electrons in 1 sublevel orbital.

Explanation:

3 0

3 years ago

Read 2 more answers

Britney added 0.05 moles of copper(II) nitrate solution to 0.1 moles of sodium hydroxide solution and

Rama09 [41]

The percent yield of copper hydroxide is 84%

<h3>Stoichiometry</h3>

From the question, we are to determine the percent yield of copper hydroxide

First, we will determine the theoretical mass

From the given balanced chemical equation, we have

Cu(NO₃)₂ + 2NaOH -- Cu(OH)₂ + 2NaNO₃

This means,

1 mole of copper(II) nitrate reacts with 2 moles of sodium hydroxide to produce 1 mole of copper hydroxide

Therefore,
0.05 mole of copper(II) nitrate reacts with 0.1 mole of sodium hydroxide to produce 0.05 mole of copper hydroxide

The theoretical number of moles of copper hydroxide that is produced is 0.05 mole

Now, for the theoretical mass

Using the formula,

Mass = Number of moles × Molar mass

Molar mass of copper hydroxide = 97.56 g/mol

Then,

Theoretical mass = 0.05 × 97.56

Theoretical mass of copper of hydroxide produced is = 4.878 g

Now, for the percent yield of copper hydroxide

Percent yield is given by the formula,

$Percent\ yield = \frac{Actual\ yield}{Theoretical\ yield} \times 100\%$

Then,

$Percent\ yield\ of\ copper\ hydroxide= \frac{4.1}{4.878}\times 100\%$

$Percent\ yield\ of\ copper\ hydroxide= 84\%$

Hence, the percent yield of copper hydroxide is 84%.

Learn more on Stoichiometry here: brainly.com/question/9372758

7 0

3 years ago