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2 years ago

Study the following unbalanced half-reaction. Which equation represents the balanced half-reaction? H2O2 ---> H2O

Chemistry

2 answers:

MA_775_DIABLO [31]2 years ago

7 0

Answer : The correct option is, $2e^-+2H^++H_2O_2\rightarrow 2H_2O$

Explanation :

The given unbalanced reaction is,

$H_2O_2\rightarrow H_2O$

(1) The right side is lacking oxygen, so we add a water molecule to it :

$H_2O_2\rightarrow H_2O+H_2O$

or we can write as,

$H_2O_2\rightarrow 2H_2O$

(2) Now we have introduced more hydrogen, so we need to balance hydrogen on the left side in acidic solution, we get

$2H^++H_2O_2\rightarrow 2H_2O$

(3) Now all the atoms are balanced but charge is not balanced. We see that the left side there are two positive charge. So, we balance the charge by adding two negative charge on the left side in the reaction, we get

$2e^-+2H^++H_2O_2\rightarrow 2H_2O$

Therefore, the correct option is, $2e^-+2H^++H_2O_2\rightarrow 2H_2O$

Aleonysh [2.5K]2 years ago

5 0

O: 1*2 = 2*1
H 2 + 2 = 2*2 

answer C hope you get it right

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1. Electronegativity is the… a. amount of energy required to remove the most loosely bound electron from an atom. b. tendency of

Kitty [74]

Answer: C.

ability of an atom to attract an electron from another atom toward itself.

Explanation:

Electronegativity is the chemical property that describes the ability of an atom to attract electron to itself. It is responsible for bond formation between atoms.

8 0

2 years ago

Read 2 more answers

A mass of 5.4 grams of aluminum (al) reacts with an excess of copper (ii) chloride (cucl2) in solution, as shown below. 3cucl2 2

horrorfan [7]

Answer:

Mass of copper produced is 19.07g

Explanation:

Let's bring out the chemical equation;

3CuCl2 + 2Al → 2AlCl3 + 3Cu

3 : 2 : 2 : 3

Upon confirming that the reaction is indeed balanced, we can proceed.

The questions asks to calculate mass of Cu formed when a mass of 5.4g of Al is being used.

From the equation, what is the relationship between Al and Cu?

2 mol of Al would react to form 3 mol of Cu

Expressing this in terms of mass, we have;

mass = no. of moles * molar mass

Mass of Aluminium = 2 * 26.98 = 53.98 g

Mass of Copper = 3 * 63.546 = 190.638g

This means;

53.98 g of Al would react to form 190.638g of Cu

So how much Cu would form from 5.4 g of Al?

This leads us to;

53.98 = 190.638

5.4 = x

Upon cross multiplication, we are left with;

x = (190.638 * 5.4) / 53.98

x = 19.07 g

Mass of copper produced is 19.07g

8 0

2 years ago

A. A nurse practitioner prepares 500. mL of an IV of normal saline solution to be delivered at a rate of 80. mL/h. What is the i

nydimaria [60]

A. Quantity of saline = 500mL
Rate of infusion = 80 mL / h
Infusion time = Quantity / Rate = 500 mL / (80 mL/hr) = 6.25 hr
b. Child weight = 72.6 lb = 32.93 kg
Medrol to be given = 1.5 mg per kg
Quantity of Medrol = 20 mg/mL
Dosage available = 20 mg/mL / 1.5 mg/kg = 13.33 kg/mL
Dosage according to body weight = 32.93 kg / 13.33 kg/mL = 2.47 mL

8 0

2 years ago

Website

vredina [299]

Answer:

volume in L = 0.25 L

Explanation:

Given data:

Mass of Cu(NO₃)₂ = 2.43 g

Volume of KI = ?

Solution:

Balanced chemical equation:

2Cu(NO₃)₂ + 4KI → 2CuI + I₂ + 4KNO₃

Moles of Cu(NO₃)₂:

Number of moles = mass/ molar mass

Number of moles = 2.43 g/ 187.56 g/mol

Number of moles = 0.013 mol

Now we will compare the moles of Cu(NO₃)₂ with KI.

Cu(NO₃)₂ : KI

2 : 4

0.013 : 4 × 0.013=0.052 mol

Volume of KI:

Molarity = moles of solute / volume in L

volume in L = moles of solute /Molarity

volume in L = 0.052 mol / 0.209 mol/L

volume in L = 0.25 L

6 0

2 years ago

Consider the following system at equilibrium where H° = -87.9 kJ, and Kc = 83.3, at 500 K. PCl3(g) + Cl2(g) PCl5(g) If the VOLUM

7nadin3 [17]

Answer:

The value of Kc C. remains the same.

The value of Qc C. is less than Kc.

The reaction must: A. run in the forward direction to reestablish equilibrium

The number of moles of Cl2 will B. decrease.

Explanation:

Le Chatelier's Principle states that if a system in equilibrium undergoes a change in conditions, it will move to a new position in order to counteract the effect that disturbed it and recover the state of equilibrium.

A decrease in volume causes the system to evolve in the direction in which there is less volume, that is, where the number of gaseous moles is less.

But temperature is the only variable that, in addition to influencing equilibrium, modifies the value of the constant Kc. So if the volume of the equilibrium system is suddenly decreased at constant temperature: The value of Kc remains the same.

As mentioned, if the volume of an equilibrium gas system decreases, the system moves to where there are fewer moles. In this case, being:

PCl₃(g) + Cl₂(g) ⇔ PCl₅(g)

The equilibrium in this case then shifts to the right because there is 1 mole in the term on the right, compared to the two moles on the left. So, The reaction must: A. run in the forward direction to reestablish equilibrium.

By decreasing the volume, and so that Kc remains constant, being:

$Kc=\frac{[PCl_{5} ]}{[PCl_{3}]*[Cl_{2} ]}=\frac{\frac{nPCl_{5} }{Volume} }{\frac{nPCl_{3}}{Volume}*\frac{nCl_{2} }{Volume} } =\frac{nPCl_{5}}{nPCl_{3}*nCl_{2}} *Volume$

where nPCl₅, nPCl₃ and nCl₂ are the moles in equilibrium of PCl₅, PCl₃ and Cl₂

so, the number of moles of Cl₂ should decrease.The number of moles of Cl2 will B. decrease.

If the reaction quotient is less than the equilibrium constant, Qc <Kc, the system will evolve to the right, the direct reaction prevailing, to increase the concentration of products. So in this case, if the reaction moves to the right, the value of Qc C. is less than Kc.

3 0

2 years ago