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
Zolol [24]
3 years ago
12

A sample of gold (Au) has a mass of 45.39 g.

Chemistry
1 answer:
professor190 [17]3 years ago
8 0
<span>1. What is the molar mass of gold?
Molar mass is a unit that expresses the mass of a molecule per one mol. The molar mass can be obtained by adding the neutron with the proton of the atoms. Gold has atomic number 79 so the proton is 79. The number of the neutron is 118. Then the molar mass would be: 79 + 118 = </span>197 g/mol<span>


</span><span>2. Calculate the number of moles of gold (Au) in the sample. Show your work. 
</span>In this question, you are given the mass of the gold and asked for how many moles the sample has. To find the number of moles you just need to divide the weight by the molar mass.
For 45.39 grams of gold, the number of moles would be:
45.39 / (197g/mol)= 0.23 moles


3. Calculate the number of atoms of gold (Au) in the sample. Show your work.Moles is unit of a number of molecules but 1 mol doesn't represent 1 molecule. The number of atoms can be obtained by multiplying the number of moles with Avogadro number. The calculation would be:
0.23 moles * (6.023 * 10^23 molecules/mol)= 1.387 * 10^23 molecules
You might be interested in
What quantity of energy would be necessary to boil water with a mass of
anygoal [31]

Answer:

i think 554 I think

Explanation:

maybe ..

6 0
3 years ago
Hey conner i miss you soooooo much and does anyone have tik tok
kherson [118]

Answer:

I have tik tok

Explanation:

6 0
3 years ago
Read 2 more answers
Which of the following is the best example of an object absorbing light? A black sweater in the sun
Lena [83]
The answer would be A
7 0
3 years ago
You will need to prepare 12 mL of 25% Sodium Phosphate Buffer (pH 4) solution for Activity 2. What volume of the stock Sodium Ph
zhuklara [117]

Assuming the concentration of stock solution is 50% sodium phosphate buffer solution, the volume of stock solution required is 6 mL and the volume of water required is 6 mL.

<h3>What volume of a stock Sodium phosphate buffer and water is needed to 12 mL of 25% sodium phosphate buffer of pH 4?</h3>

The process of preparing solutions from stock solutions of higher concentration is known as dilution.

Dilution is done with the aid of the dilution formula given below:

  • C1V1 = C2V2

where

  • C1 is the concentration of stock solution
  • V1 is the volume of stock solution required to prepare a diluted solution
  • C2 is the concentration of the diluted solution prepared
  • V2 is the final volume of the diluted solution

From the data provided:

C1 is not given

V1 is unknown

C2 = 25%

V2 = 12 mL

  • Assuming C1 is 50% solution

Volume of stock, V1, required is calculated as follows:

V1 = C2V2/C1

V1 = 25 × 12 /50

V1 = 6 mL

Therefore, the volume of stock solution required is 6 mL and the volume of water required is 6 mL.

Learn more about dilution formula at: brainly.com/question/7208546

6 0
2 years ago
How many Available electrons does CIO3, chlorate ion?
Natalija [7]
For, ClO3- there are 26 valence electrons, so total pairs of electrons are 13.
6 0
3 years ago
Other questions:
  • Convert 11.03 moles of calcium nitrate to grams
    9·2 answers
  • What do helium (He), neon (Ne), and argon (Ar) have in common?
    11·2 answers
  • gypsum is insoluble in water. you are asked to purify a sample of gypsum that is contaminated with a soluble salt.
    6·1 answer
  • NEED HELP AND WILL GIVE ALOT OF POINTS
    12·1 answer
  • 20points
    10·2 answers
  • Solve the fo<br> 1. 750 mL =<br> L
    7·1 answer
  • Color, hardness, solubility, mass, density, volume, and melting point are all examples of what type of property?
    8·1 answer
  • If a photon dropping from the n = 7 to the n = 1 level hit the surface of Au, what would be the wavelength of the ejected electr
    8·1 answer
  • The obligation of a medical coder to keep patients' medical information confidential is an example of the of ethics. __theory a)
    14·1 answer
  • Oxygen gas generated in the thermal decomposition of potassium chlorate is collected over water. The volume of gas collected is
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!