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
mario62 [17]
2 years ago
15

determine if the pennies are made of pure copper by comparing the density with that of the pure copper

Chemistry
1 answer:
zhenek [66]2 years ago
4 0

Answer:

The pennies are NOT made of pure copper since the obtained density is 9.29 g/cm3 which is greater than the density of copper which is 8.96 g/cm3.

Explanation:

You might be interested in
What does the root “thermal” mean?<br> Please Help<br> I will give you Brainliest
Nezavi [6.7K]

Answer:

If it has to do with heat, it's thermal. ... The Greek word therme, meaning “heat,” is the origin of the adjective thermal. Something that is thermal is hot, retains heat, or has a warming effect.

Explanation:

hope it helps :)

7 0
3 years ago
What is the ph of a solution of 0.700 m kh2po4, potassium dihydrogen phosphate?
GalinKa [24]
Molal or molar? There is a difference
4 0
3 years ago
The burning of magnesium is a highly exothermic reaction. How many kilojoules of heat are released when 0. 75 mol of Mg burn in
alexandr402 [8]

Taking into account the definition of enthalpy of a chemical reaction, the quantity of heat released when 0.75 moles of Mg are burned is 451.5 kJ.

<h3>Enthalpy of a chemical reaction</h3>

The enthalpy of a chemical reaction is known as the heat absorbed or released in a chemical reaction when it occurs at constant pressure. That is, the heat of reaction is the energy that is released or absorbed when chemicals are transformed into a chemical reaction.

The enthalpy is an extensive property, that is, it depends on the amount of matter present.

<h3>Heat released in this case</h3>

In this case, the balanced reaction is:

2 Mg(s) + O₂ (g) → 2 MgO(s) + 1204 kJ

This equation indicates that when 2 moles of Mg reacts with 1 mole of O₂, 1204 kJ of heat is released.

When 0.75 moles of Mg are burned, then you can apply the following rule of three: if 2 moles of Mg releases 1204 kJ of heat, 0.75 moles of Mg releases how much heat?

heat=\frac{0.75 moles of Mgx1204 kJ}{2 moles of Mg}

<u><em>heat= 451.5 kJ</em></u>

Finally, the quantity of heat released when 0.75 moles of Mg are burned is 451.5 kJ.

Learn more about enthalpy of a chemical reaction:

<u>brainly.com/question/15355361</u>

<u>brainly.com/question/16982510</u>

<u>brainly.com/question/13813185</u>

<u>brainly.com/question/19521752</u>

4 0
2 years ago
Explain the difference between weathering and erosion.
yanalaym [24]

Answer:

So, if a rock is changed or broken but stays where it is, it is called weathering. If the pieces of weathered rock are moved away, it is called erosion.

6 0
2 years ago
How many moles are in 20 grams of argon​
Sladkaya [172]

Answer:

There are 0.5 mole in 20g of argon.

Explanation:

40 g of argon = 1mole

Then 20g of argon is,

→ 1/40 × 20

→ 0.5 mole

5 0
2 years ago
Other questions:
  • To what volume will a 2.33 l sample of gas expand if it is heated from 30.0 ∘c to 300.0 ∘c?
    12·1 answer
  • It takes 770 joules of energy to raise the temperature of 50.0 g of Mercury by 110°C. What is the specific heat capacity of merc
    8·1 answer
  • Which element is heavier lead or flourine​
    11·1 answer
  • I bet half these people are kids from lhs rite now lol
    9·2 answers
  • What are four signs a chemical reaction has taken place?
    8·1 answer
  • I need help with this because it's easy for you guys but I don't understand it
    10·1 answer
  • D. The ¬_____________________ converts food into energy. It is found in both plant cells and animal cells.
    8·2 answers
  • g How many moles of NaOH are present in a sample if it is titrated to its equivalence point with 44.02 mL of 0.0885 M H2SO4? 2Na
    14·1 answer
  • 19 Down syndrome is a genetic disorder caused by the
    6·1 answer
  • An 80 ev electron impinges upon a potential barrier 100 ev high and 0. 2 nm thick. what is the probability the electron will tun
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!