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
Taya2010 [7]
3 years ago
8

Calculate the average atomic mass for the following element given information about the relevant isotopes: (Isotope 1) Mass = 20

amu; Isotopic abundance = 90.92% (Isotope 2) Mass = 21 amu; Isotopic abundance = 0.257% (Isotope 3) Mass = 22 amu; Isotopic abundance = 8.82%
Chemistry
1 answer:
polet [3.4K]3 years ago
5 0

Answer:

The average atomic mass of given element is 20.18 amu.

Explanation:

Given data:

Abundance of 1st isotope mass 20 amu = 90.92%

Abundance of 2nd isotope mass 21 amu = 0.257%

Abundance of 3rd isotope mass 22 amu = 8.82%

Average atomic mass = ?

Solution:

Average atomic mass  = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) + (abundance of 3rd isotope × its atomic mass)  / 100

Average atomic mass  = (90.92×20)+(0.257×21)+(8.82×22) /100

Average atomic mass =  1818.4 + 5.397 +194.04 / 100

Average atomic mass  = 2017.819 / 100

Average atomic mass = 20.18 amu.

The average atomic mass of given element is 20.18 amu.

You might be interested in
Which statement is in accordance with the steady state model of the universe?
Sloan [31]

E. The nuclear fuel in the stars will eventually burn out, making the universe a cold and dark place

7 0
3 years ago
Which of the following aqueous solutions will have the lowest freezing point? a. 0.75 m (NH4)3PO4 b. 1.0 m CaSO4 c. 1.0 m LiCl d
Nataly [62]

Answer: a. 0.75m (NH4)3PO4 will have the lowest freezing point .

Explanation: Freezing point decreases as the concentration of the solute substance increases. Assuming the same solvent for all of them, for instance water.

∆T= i.Kf.b

∆T= freezing point depression

i= vant Hoff factor

Kf= molality

Assuming water to be the solvent for all Kf=1.86°C/M

VANT HOFF FACTORS :

For (NH4)3PO4

This has 3 ionic bonding and 1 covalent bonding making it 4 bond

Therefore i=4

For CaSO4

This has 1 metallic bond and 1 covalent bond making it 2 bond.

Therefore i=2

For LiCl

This has 1 metallic bond and 1 non metallic bond making it 2 bond.

Therefore i=2

For CH3OH

This has only 1 covalent bond.

Therefore i=1

MOLALITY:

(NH4)3PO4 = 0.75M

CaSO4= 1.0M

LiCl= 1.0M

CH3OH= 1.5M

FREEZING POINT DEPRESSION:

For (NH4)3PO4

∆T= 4×0.75×1.86=5.58°C

For CaSO4

∆T= 2×1.0×1.86=3.72°C

For LiCl

∆T = 2×1.0×1.86= 3.72°C

For CH3OH

∆T= 1×1.5×1.86=2.79°C

REMEMBER THE HIGHER THE FREEZING POINT DEPRESSION THE LOWER THE FREEZING POINT.

FREEZING POINT DEPRESSION IS THE CHANGE IN THE FREEZING POINT PROPORTIONAL TO THE AMOUNT OF SOLUTE ADDED THE THE SOLUTION.

THEREFORE THE ONE WITH THE LOWEST FREEZING POINT IS (NH4)3PO4

4 0
3 years ago
2KCIO3 ----------&gt; 2KCI + 302<br> How many moles of KCIO3 are needed to make 3.5 moles of KCL?
lyudmila [28]

Answer:

3.5 mol KClO3

Explanation:

Given 3.50 moles of KCl as the target amount in the problem, used the coefficient of the balanced chemical reaction involved to determine the number of moles of potassium perchlorate needed.

x mole of  KClO3  = 3.5 mol  KCl x [(2 mol KCl)/ (2 mol KClO3)] = 3.5 mol KClO3

x mole of  KClO3 = 3.5 mol KClO3

3 0
3 years ago
Select the correct answer.
Gennadij [26K]

The correct answer is A. An element cannot be separated into simpler substances or converted into another substance by chemical processes. Elements are the most simplest form of the chemicals. They are what we see in the periodic table.

Please mark brainliest. :)

8 0
3 years ago
Please help!!! I can’t figure it out!
marin [14]

Answer:

The third answer

Explanation:

6 0
3 years ago
Other questions:
  • A mushroom would most likely eat
    8·1 answer
  • Constance is making a vegetable soup that contains carrots, beans, water, salt, pepper, bits of ham, and onions. the soup has to
    12·1 answer
  • What are the factors that affect the rate of dissolution
    15·2 answers
  • The atomic number of magnesium (mg) is 12. this is also the number of which of the following
    9·1 answer
  • Near Cozumel, Mexico, a scuba diver goes down 60 ft to look at the sea creatures. As she descends, the air pressure increases. W
    15·1 answer
  • Which of the following is not an indication of a chemical change?
    7·2 answers
  • Please Help If You Know The Answer 15 Points A fallow and a thanks!!
    8·2 answers
  • What is the full name for an atom with 20 protons and 14 neutrons?
    7·1 answer
  • The substances in a chemical reaction that are combined or separated to form new substances are the _______.
    5·2 answers
  • Please help me, im studying for finals and i need an answer to this question! Will mark brainliest for the answers that are the
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!