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
ad-work [718]
3 years ago
12

A jeweler guarantees that a piece of jewelry is at least 95% gold, by mass. You consider buying a piece of gold jewelry that wei

ghs 9.85g and has a volume of 0.675cm3. The jewelry contains only gold and silver. Suspicious of the jeweler, you look up the density of gold and silver, they are 19.3g/cm3 and 10.5g/cm3, and do a quick calculation to find out the % by mass of gold. Is the jeweler trying to cheat you?
Chemistry
1 answer:
ELEN [110]3 years ago
8 0
The density of the sample is:
Density = mass / volume
Density = 9.85 / 0.675
Density = 14.6 g/cm³

If the sample has 95% gold, and 5% silver, its density should be:
0.95 x 19.3 + 0.05 x 10.5
Theoretical density = 18.9 g/cm³

The difference in theoretical and actual densities is very large, making it likely that the jeweler was not telling the truth.
You might be interested in
Earth's axis is tilted. Tell what would happen if it was vertical instead.
slamgirl [31]
I think the like term is 6 hope this is right
7 0
3 years ago
Read 2 more answers
Question 7 of 15
Crazy boy [7]

Answer: 0.4 moles

Explanation:

Given that:

Volume of gas V = 11L

(since 1 liter = 1dm3

11L = 11dm3)

Temperature T = 25°C

Convert Celsius to Kelvin

(25°C + 273 = 298K)

Pressure P = 0.868 atm

Number of moles N = ?

Note that Molar gas constant R is a constant with a value of 0.00821 atm dm3 K-1 mol-1

Then, apply ideal gas equation

pV = nRT

0.868atm x 11dm3 = n x (0.00821 atm dm3 K-1 mol-1 x 298K)

9.548 atm dm3 = n x 24.47atm dm3mol-1

n = (9.548 atm dm3 / 24.47atm dm3 mol-1)

n = 0.4 moles

Thus, there are 0.4 moles of the gas.

3 0
3 years ago
If 11.5 ml of vinegar sample (d=1g/ml) is titrated with 18.5 ml of standardized Sodium hydroxide
insens350 [35]

Answer:

4.83% of acetic acid in the vinegar

Explanation:

3 0
3 years ago
Which of the following is the correct equation for the reaction below?
fenix001 [56]

Answer:

Option C.

2 Mg (s) + O₂(g) →  2MgO (s)

Explanation:

Two moles of magnesium solid react with one mol of oxygen gas to

form two moles of magnesium-oxide solid

2 Mg (s) + O₂(g) →  2MgO (s)

That's the reaction for the magnessium oxide's formation.

Be careful cause we do not say molecules, they are moles.

The stoichiometry indicates the number of moles that react and the moles which are produced.

It is a redox reaction, because the magnessium is oxidized and the oxygen is reduced. Both elements, changed the oxidation states.

4 0
3 years ago
Read 2 more answers
Transition metals can be found in Families 3 through 12 on the periodic table. What property do transition metals share?
Vedmedyk [2.9K]
The answer might be C
8 0
3 years ago
Read 2 more answers
Other questions:
  • Reaction rate depends on how often molecules come into contact with each other, the way in which they come together, and the amo
    13·2 answers
  • 1. what is volume?
    15·2 answers
  • Which of the following has three electrons in its valence shell?
    7·2 answers
  • Particles of Substance X are dispersed in water to form a colloid. Which describes the electrical charges on the particles of Su
    9·1 answer
  • Batteries involve the flow of electricity from one metal to another. What happens to these metals to cause the batteries to, eve
    11·1 answer
  • Which one is it (it’s multiple choice too)
    13·1 answer
  • Consider the intermediate chemical reactions. 2 equations. First: upper C a (s) plus upper C upper O subscript 2 (g) plus one ha
    7·1 answer
  • Explain why this compound is not a hydrocarbon. *<br> (2 points)
    12·2 answers
  • Calculate the number of moles of magnesium, chlorine, and oxygen atoms in 5.40 moles moles of magnesium perchlorate, Mg(ClO4)2Mg
    5·1 answer
  • Someone please help me with the two I got wrong
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!