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
julia-pushkina [17]
3 years ago
7

A 130.3 g piece of copper (specific heat 0.38 J/g・°C) is heated and then placed into 400.0 g of water initially at 20.7°C. The w

ater increases in temperature to 22.2°C. What is the initial temperature of the copper? (The specific heat of water is 4.18 J/g・°C).
Chemistry
1 answer:
mylen [45]3 years ago
4 0

Answer:

Approximately 72.9\; \rm ^\circ C, assuming that this system is insulated properly.

Explanation:

Calculate the amount of energy that the water here has gained (using the increase in its temperature.)

\begin{aligned} Q(\text{water}) &= c(\text{water}) \cdot m(\text{water}) \cdot \Delta T(\text{water}) \\ &=4.18 \times 400.0 \times (22.2 - 20.7) \approx 2508.0\; \rm J \end{aligned}.

Assume that this system (copper and water) is well-insulated and has no heat exchange with its surroundings. The amount of energy that water gained should be equal to the of energy that copper has lost. However, the sign of the energy change of copper should be negative because copper had lost energy:

Q(\text{copper}) = -Q(\text{water}) \approx -2508.0\; \rm J.

Calculate the temperature change of this piece of copper. Note, that this temperature change is the difference between the initial temperature of the copper piece and the final temperature 22.2\; \rm ^\circ C of the system.

\begin{aligned}\Delta T(\text{copper}) &= \frac{Q(\text{copper})}{c(\text{copper}) \cdot m(\text{copper})} \approx \frac{-2508.0}{130.3 \times 0.38} \approx 50.65\; \rm ^\circ C\end{aligned}.

Calculate the initial temperature of this piece of copper given its final temperature and the change to its temperature:

\begin{aligned}T(\text{copper, initial}) &= T(\text{copper, final}) - \Delta T(\text{copper}) \\ &\approx 22.2 + 50.65 \approx 72.9\; \rm ^\circ C\end{aligned}.

You might be interested in
I've asked before and gotten spammed hopefully I won't get spammed this time please help me with this someone.​ pls help anyonw
elena55 [62]

Answer:

See below!

Explanation:

A.  The picture of the graph is attached.  You can tell the amount of protons in an element by looking at the periodic table.  The elements are ordered by the number of protons in an element.

B.  Carbon and silicon are at the peaks of the chart.  The peak is the highest point in a graph.

C.  The elements belong to the non-metal group.

D.  The halogens are non-metals, and their vapors are colorless.

The halogens are toxic to humans.

Halogen molecules are made of two atoms; they are diatomic.

Halogens react with non-metals to form crystalline compounds that are salts.

The halogens get less reactive going down the group on the periodic table.

Halogens can bleach vegetable dyes and kill bacteria.

E.  The picture of the table is attached.  To figure which numbers to put where, you need to pay attention to the other numbers.  The halogens follow a trend with each of these properties.  You have to put in the numbers that fit in among the other numbers.

3 0
3 years ago
The conversion of 37 ˚C to K
77julia77 [94]

Answer:

310.15

Explanation:

c + 273.15 = k

37+ 273.15 = 310.15

8 0
3 years ago
Read 2 more answers
Which element does this Bohr model represent? (look at a periodic table if needed)
Serjik [45]
Circulating round the nucleus are the electrons in various orbits of different energy levels. Electrons are negatively charged and represented by the symbol 'e'. In the given image the number of protons are -6. Hence the element in question is Carbon as Carbon has the atomic number 6.
6 0
3 years ago
Use the formation reactions below such that when added together, they match the balanced equation for the combustion of methane.
muminat

Answer:

ΔH of the reaction is -802.3kJ.

Explanation:

Using Hess's law, you can know ΔH of reaction by the sum of ΔH's of half-reactions.

Using the reactions:

<em>(1) </em>Cgraphite(s)+ 2H₂(g) → CH₄(g) ΔH₁ = −74.80kJ

<em>(2) </em>Cgraphite(s)+ O₂(g) → CO₂(g) ΔH₂ = −393.5k J

<em>(3) </em>H₂(g) + 1/2 O₂(g) → H₂O(g) ΔH₃ = −241.80kJ

The sum of (2) - (1) produce:

CH₄(g) + O₂(g) → CO₂(g) + 2H₂(g) ΔH' = -393.5kJ - (-74.80kJ) = -318.7kJ

And the sum of this reaction with 2×(3) produce:

CH₄(g) + 2 O₂(g) → CO₂(g) + 2H₂O(g) And ΔH = -318.7kJ + 2×(-241.80kJ) =

<em>-802.3kJ</em>

7 0
3 years ago
Consider a mystery compound having the formula MxTy. If the compound is not an acid, if it contains only two elements, and if M
valkas [14]

Answer:

d.) It is a binary molecular compound.

Explanation:

The compound in question has a formula M{x}T_{y}. The compound is not acidic in nature and the element 'M' is not a metal. This shows that the compound does not contain any metal. Based on the definition of a binary molecular compound as a compound comprising elements that are not metals. Therefore, the compound is obviously a binary molecular compound.

7 0
3 years ago
Read 2 more answers
Other questions:
  • A forensic chemist is given a white powder for analysis. She dissolves 0.50 g of the substance in 8.0 g of benzene. The solution
    5·1 answer
  • Define organic chemistry
    10·2 answers
  • Next to each formula, write the number of atoms of each element found in one unit of the compound
    10·1 answer
  • Please help i don't remember this answer
    8·1 answer
  • Please answer! need it soon
    12·1 answer
  • A 540 mL sample of a 0.100 M formate buffer, pH 3.75, is treated with 9 mL of 1.00 M KOH. What is the pH following this addition
    9·1 answer
  • In addition to specific heat capacity and density, could yo use another physical property such as color to determine the identit
    11·1 answer
  • Can you identify what object is being represented by the model on the right?
    13·2 answers
  • What is the LD50 of a substance?
    12·1 answer
  • Which of the following is an example of climate?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!