5. After a day of testing race cars, you decide to

How many moles of copper are needed to react with sulfur to produce 2.9 moles of copper (I) sulfide

dalvyx [7]

Answer:

5.8 moles of copper are needed to react with sulfur to produce 2.9 moles of copper (I) sulfide.

Explanation:

$2Cu+S\rightarrow Cu_2S$

Moles of copper(I) sufide = 2.9 mol

According to reaction, 1 mole of copper(I) sulfide is obtained from 2 moles of copper, then 2.9 moles of copper(I) sulfide will be obtained from :

$\frac{2}{1}\times 2.9 mol=5.8 mol$ copper

5.8 moles of copper are needed to react with sulfur to produce 2.9 moles of copper (I) sulfide.

4 0

3 years ago

A 500.0-mL buffer solution is 0.100 M in HNO2 and 0.150 M in KNO2. Determine if each addition would exceed the capacity of the b

likoan [24]

Answer:

no one additions exceed the capacity of the buffer

Explanation:

given

Volume buffer = 500.0 mL = 0.5 L

mol HNO₂ = 0.5 L × 0.100 mol/L = 0.05 mol HNO₂

mol NO₂⁻ = 0.5 L × 0.150 mol/L = 0.075 mol NO₂⁻

solution

we know when any base more than 0.05 (HNO2) than exceed buffer capacity

and when any base more than 0.075 (KNO2) than exceed buffer capacity

when we add 250 mg NaOH (0.250 g)

than molar mass NaOH =40 g/mol

and mol NaOH = 0.250 g ÷ 40g/mol

mol NaOH = 0.00625 mol

0.00625 mol NaOH will be neutralized by 0.00625 mol HNO₂

so it would not exceed the capacity of the buffer.

and

when we add 350 mg KOH (0.350 g)

than molar mass KOH =56.10 g

and mol KOH = 0.350 g ÷ 56.10 g/mol

mol KOH = 0.0062 mol

here also capacity of the buffer will not be exceeded

and

now we add 1.25 g HBr

than molar mass HBr = 80.91 g/mol

and mol HBr = 1.25 g ÷ 80.91 g/mol

mol HBr = 0.015 mol

0.015 mol Hbr will neutralize 0.015 mol NO₂⁻

so the capacity will not be exceeded.

and

we add 1.35 g HI

molar mass HI = 127.91 g/mol

so mol HI = 1.35 g ÷ 127.91 g/mol

mol HI = 0.011 mol

capacity of the buffer will not be exceed

3 0

3 years ago

The symbol of an element represents one atom of that element Ba=

Mama L [17]

Barium, it's an earthy alkaline metal it's atomic number is 56

4 0

3 years ago

How many grams of NaOH are produced from 20 grams of Na2Co3

Mariulka [41]

Answer:

1400

Explanation:

4 0

3 years ago

A galvanic cell consists of a Cu(s)|Cu2+(aq) half-cell and a Cd(s)|Cd2+(aq) half-cell connected by a salt bridge. Oxidation occu

Kryger [21]

Answer:

$Cd(s)|Cd^{2+}(aq) || Cu^{2+}(aq)|Cu(s)$

Explanation:

A galvanic cell is composed of two electrodes immersed in a suitable electrolyte and connected via a salt bridge. One of the electrodes serves as a cathode where reduction or gain of electrons takes place. The other half cell functions as an anode where oxidation or loss of electrons occurs.

The representation is given by writing the anode on left hand side followed by its ion with its molar concentration. It is followed by a salt bridge. Then the cathodic ion with its molar concentration is written and then the cathode.

As it is given that cadmium acts as anode, it must be on the left hand side and copper must be on right hand side.

$Cd(s)|Cd^{2+}(aq) || Cu^{2+}(aq)|Cu(s)$

6 0

3 years ago