1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
SCORPION-xisa [38]
3 years ago
5

For an alloy that consists of 93.1 g copper, 111.7 g zinc, and 4.0 g lead, what are the concentrations of (a) Cu, (b) Zn, and (c

) Pb in weight percent? The atomic weights of Cu, Zn, and Pb are 63.54, 65.39, and 207.2 g/mol, respectively.
Chemistry
1 answer:
Andrew [12]3 years ago
5 0

Answer:

(a) weight percent of Cu = 44.59%

(b) weight percent of Zn = 53.49%

(c) weight percent of Pb = 1.91%

Explanation:

Given: Alloy contains- Cu=93.1 g, Zn=111.7 g, Pb=4.0 g

Therefore, the total mass of the alloy (m) = mass of Cu (m₁) + mass of Zn (m₂)+ mass of Pb (m₃)

m= 93.1 g + 111.7 g + 4.0 g = 208.8 g

(a) weight percent of Cu = (m₁ ÷ m)× 100% =  (93.1 g ÷ 208.8 g)× 100% =44.59%

(b) weight percent of Zn = (m₂ ÷ m)× 100% =  (111.7 g ÷ 208.8 g)× 100% =53.49%

(c) weight percent of Pb = (m₃ ÷ m)× 100% =  (4.0 g ÷ 208.8 g)× 100% =1.91%

You might be interested in
One kilogram of water at 100 0C is cooled reversibly to 15 0C. Compute the change in entropy. Specific heat of water is 4190 J/K
mina [271]

Answer:

The change in entropy is -1083.112 joules per kilogram-Kelvin.

Explanation:

If the water is cooled reversibly with no phase changes, then there is no entropy generation during the entire process. By the Second Law of Thermodynamics, we represent the change of entropy (s_{2} - s_{1}), in joules per gram-Kelvin, by the following model:

s_{2} - s_{1} = \int\limits^{T_{2}}_{T_{1}} {\frac{dQ}{T} }

s_{2} - s_{1} = m\cdot c_{w} \cdot \int\limits^{T_{2}}_{T_{1}} {\frac{dT}{T} }

s_{2} - s_{1} = m\cdot c_{w} \cdot \ln \frac{T_{2}}{T_{1}} (1)

Where:

m - Mass, in kilograms.

c_{w} - Specific heat of water, in joules per kilogram-Kelvin.

T_{1}, T_{2} - Initial and final temperatures of water, in Kelvin.

If we know that m = 1\,kg, c_{w} = 4190\,\frac{J}{kg\cdot K}, T_{1} = 373.15\,K and T_{2} = 288.15\,K, then the change in entropy for the entire process is:

s_{2} - s_{1} = (1\,kg) \cdot \left(4190\,\frac{J}{kg\cdot K} \right)\cdot \ln \frac{288.15\,K}{373.15\,K}

s_{2} - s_{1} = -1083.112\,\frac{J}{kg\cdot K}

The change in entropy is -1083.112 joules per kilogram-Kelvin.

7 0
3 years ago
2.When copper (II) nitrate reacts with sodium hydroxide, copper (11) hydroxide is produced.
Ann [662]

Answer:

 

2Cu + S ~~~> Cu2S Copper (C) reacts with sulfur (S) to form copper sulfide as shown in the equation. A scientist adds 12.7 grams of Cu to 3.2 grams of S to start the reaction.

Explanation:

7 0
3 years ago
Suppose you needed to measure exactly 15.0 mL of water for an
s344n2d4d5 [400]

Answer:

A 50-mL volumetric cylinder with 0.1-mL accuracy scale should be used for this purpose since three significant figures of accuracy are required.

Explanation:

Hello,

A 50-mL volumetric cylinder with 0.1-mL accuracy scale should be used for this purpose since three significant figures of accuracy are required.

Best regards.

6 0
3 years ago
Read 2 more answers
In a metal what is not given an assigned location and thus can drift
Allushta [10]
In a metal, "Electrons" <span> is not given an assigned location and thus can drift

In short, Your Answer would be Option C

Hope this helps!</span>
6 0
3 years ago
Which two particles are found in the center of an atom?
seraphim [82]

Answer:

B) Protons and Neutrons

Explanation:

In every atom, there is a Nucleus which contains protons and Neutrons. Protons being positive and Neutrons not having a charge (neutral).  

6 0
3 years ago
Read 2 more answers
Other questions:
  • It takes 5.2 minutes for a 4.0 g sample of francium-210 to decay until only 1.0 g is left. What is the half-life of francium-210
    10·2 answers
  • I need alot of help.
    12·1 answer
  • The caloric content of 0.50 cup of cottage cheese is 1.10 x 102 kcal. This is the amount of energy released when 0.50 cup of cot
    14·1 answer
  • Calculate the molar volume occupied by 1 mole of N2 using the van der Waals equation in the form of virial expansion at (a) its
    6·1 answer
  • The bottom number on each element of a on the periodic table is called
    7·1 answer
  • When ironing clothes, the primary method of heat transfer is A) conduction. B) convection. C) insulation. D) radiation.
    11·2 answers
  • all of the following electromagnetic waves possess high energy that will damage the human body if overexposed, except _____. ult
    7·1 answer
  • Which of the following would have the most kinetic energy?
    14·1 answer
  • A certain gas is found in the exhaust of automobiles and power plants. Consider a 1.53 L sample of a gas at a pressure of 5.6 x
    11·1 answer
  • If I have 4.5 liters of gas at a temperature of 33 0C and a pressure of 6.54 atm, what will be the pressure of the gas if I rais
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!