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
algol [13]
3 years ago
12

What do you think will happen if you pinch your arm after you stub your toe?

Chemistry
2 answers:
Maru [420]3 years ago
6 0
It would distract the pain in your toe. That's all I got
elena-14-01-66 [18.8K]3 years ago
6 0

it would distract the pain

You might be interested in
Why is the anatomy of the human body not a general reason to study chemistry. Need help for a good reply.
ivolga24 [154]
Anatomy's a biology topic!
8 0
3 years ago
A 20g piece of lead absorbs 566 joules of heat and its temperature changes from 35 oC to 195 oC. Calculate the specific heat.
Alja [10]

Answer:

  • <u>Question 1: 0.2J/(gºC)</u>
  • <u>Question 2: 6,000J</u>
  • <u>Question 3: 300J</u>
  • <u>Question 4: 80g</u>
  • <u>Question 5: 74ºC</u>
  • <u>Question 6: 50g</u>

<u></u>

Explanation:

Question 1.<em> A 20g piece of lead absorbs 566 joules of heat and its temperature changes from 35º oC to 195º C. Calculate the specific heat.</em>

<em />

The thermal energy equation is:

  • Q = m × C × ΔT

<em />

Substitute and solve for C:

  • 566J = 20g × C × (195ºC - 35ºC)
  • C = 566J / (20g × 160ºC)
  • C = 0.177 J/(gºC) ≈ 0.2J/(gºC)

<em />

You must round to one significant figure because one factor has one significant figure).

<em />

<em />

Qustion 2.<em> 40g of water is heat at 40ºC and the temperature rise to 75ºC. What is the amount of heat needed for the temperature to rise? (specific heat of water is 4.184 J/gºC)</em>

<em />

Use the thermal energy equation again:

  • Q = m × C × ΔT

<em />

Substitute and compute:

  • Q = 40g × 4.184 J/gºC × (75ºC - 40ºC)
  • Q = 5,857.6J

Round to one significant figure: 6,000J

<em />

Question 3. <em>Graphite has a mass of 50g and a specific heat of 0.420 J/gºC. If graphite is cooled from 50ºC to 35ºC, how much energy was lost?</em>

  • Q = m × C × ΔT
  • Q = 50g × 0.420J/gºC × (35ºC - 50ºC)
  • Q = 315J

Round to one significant figure (because 50g has one significant figure)

  • Q = 300J

<em />

Question 4.<em> </em><em>Iron has a specific heat of 0.712 J/gºC. A piece of iron absorbs 3000J of energy and undergoes a temperature change totaling 50ºC, What is the mass of iron?</em>

<em />

  • Q = m × C × ΔT

Solve for m:

  • m = Q / (C × ΔT)

Substitute and compute:

  • m = 3,000J / (0.712J/gºC × 50ºC)
  • m = 84.26 g ≈ 80 g (rounded to one significant figure, because the factor 3,000J has one significant figure).

Question 5. <em>If 400g of an unknown solution at 70ºC loses 7500 J of heat, what is the final temperature of the unknown solution. The unknown solution has a specific heat of 4.184 J/gºC.</em>

<em />

  • Q = m × C × ΔT

<em />

Q is negative, since it is released.

Substitute and solve for T:

  • - 7,500J = 400g × 4.184J/gºC × (T - 70ºC)

  • T = - 7500J / 400g × 4.184J/gºC) + 70ºC

  • T = 74ºC

<em />

If you round to one significant figure you cannot tell the temperature difference, thus leave two significant figures.

<em />

Question 6. <em>How many grams of water would require 9500J of heat to raise the temperature from 50ºC to 100ºC</em>

  • Q = m × C × ΔT

Subsitute:

  • 9,500J = m × 4.184J/gºC × (100ºC - 50ºC)

Solve for m and compute:

  • m = 9,500J / (4.184J/gºC × 50ºC)

  • m = 45g

Since the temperatures indicate one singificant figure, the mass should be rounded to one significant figure:

  • m = 50g.
8 0
3 years ago
What is the mass number of 80Br
Amanda [17]
Mass number of an element write in bottom of it!

So, there 80 would be the mass number of ₈₀Br.

Hope this helps!
4 0
3 years ago
Convert 485 milligrams into grams
Zielflug [23.3K]

Answer:

look at the picture above

5 0
3 years ago
Read 2 more answers
Do meteorologists need instruments
storchak [24]

Meteorological instruments are the hardware used to test the condition of the climate at a given time. Every science has its very own interesting arrangements of lab hardware.

6 0
3 years ago
Read 2 more answers
Other questions:
  • What is the justification required to make an arrest?
    6·1 answer
  • During which of the fallowing chemical changes does a precipitate form??
    7·1 answer
  • CO is a primary pollutant.
    12·2 answers
  • Balance this redox reaction occurring in acidic media:
    15·1 answer
  • A chemist has some 40% acid solution, some 60% acid solution, and a wholebunch of free time. How many liters of each should be u
    7·1 answer
  • A classification of matter which stipulates that the compound must contain carbon is called
    9·1 answer
  • After scientists get the results of their experiments, they...
    5·1 answer
  • Sally has touched a hot pan on the stove and burnt her hand. This example shows what type of heat transfer?
    12·1 answer
  • Compared to compounds with network structures, compounds arranged in molecules (covalent bonds) have ____________ melting points
    12·1 answer
  • WHaty are the Chemical properties of Oxygen?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!