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 water 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).
Answer:
Approximately [tex]72.9\; \rm ^\circ C[/tex], 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.)
[tex]\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}[/tex].
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:
[tex]Q(\text{copper}) = -Q(\text{water}) \approx -2508.0\; \rm J[/tex].
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 [tex]22.2\; \rm ^\circ C[/tex] of the system.
[tex]\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}[/tex].
Calculate the initial temperature of this piece of copper given its final temperature and the change to its temperature:
[tex]\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}[/tex].
Give two examples. What is prey?
Answer: deer and a rabbit or zebra
Please Help. Will mark as Brainliest
Answer:
You are correct. The answer is [tex]X_{3} Z[/tex].
All elements in the same group (Column) on a periodic table have what in common?
If I mix 10 grams of baking soda with 15 grams of vinegar, what should the mass
of the water and carbon dioxide gas be when added together?
Answer:
25 grams
Explanation:
10 +15 =25 you welcome
What body system controls the brain, spinal cord, nerves, and sense organs?
Answer:
The central nervous system
The emission spectrums are known for the elements below. Line spectra for boron, lithium, hydrogen, helium, potassium and unknown sample. Boron has 3 purple lines, 1 blue line, 2 blue-green lines and 2 orange lines. Lithium has 2 purple lines, 2 blue lines, 2 blue-green lines, 1 orange line and 1 red line. hydrogen has one line of each purple, blue, blue-green and red. helium has 3 purple lines, 3 blue lines, 3 blue-green lines 1 yellow line and 2 red lines. Potassium has 8 purple lines, 6 blue-green lines, 10 green lines, 3 yellow lines, 2 orange lines and 6 red lines. The unknown sample has Potassium has 8 purple lines, 6 blue-green lines, 10 green lines, 3 yellow lines, 2 orange lines and 6 red lines. What elements are in the unknown sample? Check all that apply. boron lithium hydrogen helium potassium
Answer:
The Answer is (B) lithium and (E) potassium
The elements are in the unknown sample of emission spectrums is lithium and potassium. correct options are B and E.
What is emission spectrums?The emission spectrum of elements are is a formation of different types of lines of different colors and are of different wavelengths when their is emission of the light through a chemical substance is known to be emission spectrums.
The line of red color have the longest wavelength and can be measured easily with the help of spectrophotometer during the emission of light passing through it.
Therefore, elements are in the unknown sample of emission spectrums is lithium and potassium. correct options are B and E.
Learn more about emission spectrum, here:
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Which material is typically used as a thermal insulator
Answer: plastic, wood, rubber
Explanation:
Answer:
Lots of items.
Explanation:
Fiber, mineral wool, and corks.
I WILL GIVE BRAINLIEST! ANSWER ASAP! If 50 grams of vinegar and 10 grams of baking soda are poured into a container, what will the final mass of the products be?
Answer: Wouldn't that just be 60 grams?
Explanation:
50+10=60
The concentration of two reactants is decreased by the same amount. How
will this change in concentration affect the reaction?
A. The reaction rate will increase by the same amount the concentrations were increased
B. The change in concentration will affect the rate of the reaction according to the rate law
C. The change in the reaction rate depends on the balanced chemical equation
D. The reaction rate will decrease by the same amount the concentrations were decreased
Which statement best describes a scientific theory?
A) It is a scientific fact that no longer requires any evidence to support it.
B) It is a general statement that is supported by many scientific observations.
C) It is an educated guess that can be tested by experimentation.
D) It is a collection of data designed to provide support for a prediction.
Answer:
B
Explanation:
Just because it is a theory doesnt mean it does not need evidence or odservations.
Answer:
it’s c
Explanation:
it’s c
Help Please!! (The Question is in the picture!)
Answer:
the answer that best describe the two methods is c
A rectangular solid has a length of 3 cm height of 4 cm and a Width of My 5 cm what is a solid volume
Volume = length x width x height
Volume = 3cm x 5cm x 4cm
Volume = 60cm3
Hope this helps! :)
The economy of each region was shaped by all of the following factors, except:
A. Geography
B. Climate
C. Language
D. Population
Answer:
Language
Explanation:
this is very obvious not to be mean
sapling is to a tree as a _______ is to a horse... help meee
metalloids tend to be
Answer:
Metalloids tend to be shiny like metals but brittle like nonmetals. Because they are brittle, they may chip like glass or crumble to a powder if struck. Other physical properties of metalloids are more variable, including their boiling and melting points, although all metalloids exist as solids at room temperature.
Explanation:
9.87 x 10^-5km - 8.76 x 10^-6km
WHAT IS THE DENSITY OF A BLOCK WITH A
VOLUME OF 24 ML AND A MAS 3.2 G?
Answer:
The answer is 7.5 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
So we have
[tex]density = \frac{24}{3.2} \\ [/tex]
We have the final answer as
7.5 g/mLHope this helps you
In 1909, Ernest Rutherford performed an experiment to explore the atomic structure. In his experiment, he projected high-speed α particles onto a thin gold foil. He found that all α particles did not follow the same path. Most of the particles passed through the foil without any scattering, implying that most of the space in an atom is empty. Some particles were scattered at a large angle, and very few of them scattered back in the direction from which they had come. Based on these observations, Rutherford proposed an atomic model, which is known as Rutherford’s atom.
On the basis of Ruthertord's experimentel observations, which of the following statements describes the structure of the atom according to Rutherford's atomic model?
A. In an aborn, negatively charged electrons are dispersed in the space surrounding tho positively charged nucleus of an atom
B. ln an atom, au of the positive and negative charges are randomly distributed.
C. In an atom, the postive eherges are ocated in a smal core wrin the atom cated the nucleus
D. In an atom, positively charged porticles are dispersed in the space surounding the negiively charged sphere
Answer:
A. In an aborn, negatively charged electrons are dispersed in the space surrounding tho positively charged nucleus of an atom
C. In an atom, the positive energies are located in a small core within the atom called the nucleus
Explanation:
the answers are options A and C.
In the year 1909, Emest Rutherfords performed this experiment from which his atomic model came about. The atomic model gave a description of atom to be a small core which is dense and which has a nucleus that is positively charged. Rutherford in his model tries to give a description of the atom as mainly just empty space and that it has electrons going through a static or fixed charged nucleus. While doing this they are in sets and their paths are predictable.
The elementary gas-phase reaction
A → B
takes place isobarically and isothermally in a PFR where 63.2% conversion is achieved. The feed is pure A. It is proposed to put a CSTR of equal volume upstream of the PFR. Based on the entering molar flow rate to A to the first reactor, what will be the intermediate from the CSTR, X1, and exit conversion from the PFR, X2, based on the feed to first reactor?
Answer:
Xa1 = 0.5
Xa2 = 0.815
Explanation:
Elementary gas-phase reaction
A → B taking place isobarically and isothermally and the feed is Pure
conversion rate = 63.2%
The intermediate from the CSTR (XA1 ) = 50%
conversion in the PFR at the exit ( XA2 ) = 0.815
Attached below is the detailed
Different kind of London are used in eyeglasses to help people with eye conditions
Answer:
true
Explanation:
If 20.0 kilocalories of energy were added to 80.0 g of water, what change in temperature would be observed?
Please explain how.
Answer:
250 °C.
Explanation:
From the question given above, the following data were:
Heat (Q) required = 20.0 kilocal
Mass (M) of water = 80 g
Change in temperature (ΔT) =.?
Next, we shall convert 20.0 Kilocalories to calories. This can be obtained as shown below:
1 kilocal = 1000 Cal
Therefore,
20 kilocal = 20 kilocal × 1000 Cal / 1 kilocal
20 kilocal = 20000 calories
Therefore, 20 kilocalorie is equivalent to 20000 calories.
Finally, we shall determine the change in temperature observed as follow:
Heat (Q) required = 20000 Cal
Mass (M) of water = 80 g
Specific heat capacity (C) of water = 1 Cal /gºC
Change in temperature (ΔT) =.?
Q = MCΔT
20000 = 80 × 1 × ΔT
20000 = 80 × ΔT
Divide both side by 80
ΔT = 20000 / 80
ΔT = 250 °C
Therefore, the change in temperature observed is 250 °C
Which of the following groups makes a neutral salt of the form AB
Answer:
Groups II and VI
Explanation:
Hello.
In this case, regarding cations from groups I whose oxidations states are +1, II whose oxidation states are +2 and III whose oxidation states are +3 we can see that when they combine with nonmetallic anions they exchange the charges via subscripts. In such a way, when bonding for instance calcium ions with sulfide ions, we obtain:
[tex]Ca^{2+}S^{2-}=Ca_2S_2[/tex]
Which can be simplified to give:
[tex]CaS[/tex]
If we do the same for oxygen, selenium and tellurium, we find the same form since nonmetals from group VIA could form anions with -2 as they need two electrons to attain the octet, therefore, answer is groups II and VI.
Regards.
is water a mineral? HELP ASAP!!!!
Answer:
Water is not a mineral because it is not a solid.
Explanation: If water were turned into ice then it would be considered if water were turned into ice then it would be considered a mineral.
How does rainfall affect a biome !?!?!!??!
Explain how balanced and unbalanced forces affect an object's motion differently.
If 2 g of element X combines with 7 g of element Y to form compound XY, how many grams of Y
are needed to form compound XY2?
(1 Point)
Answer:
14g of Y to form the compound XY₂
Explanation:
In the compound XY, you have 1 mole of X and 1 mole of Y. Thus, you can imagine the molar mass of X is 2g/mol and molar mass of Y is 7g/mol.
Now, in the compound XY₂, you have 1 mole of X but 2 moles of Y.
If you have 2g of X, in this case you will need:
2 moles Y * (7g / mol) =
14g of Y to form the compound XY₂
The amount of element Y needed to form compound XY2 is; 14g of element Y.
From the law of conservation of mass which states that;
Matter can never be created nor destroyed.
By stoichiometry;
Since:
7 g of element Y to form compound XY(y =1)
a g of element Y to form compound XY2(y =2)
In essence,
a g = (2 × 7g)/1
a = 14g
Therefore, 14g of element Y is needed to form compound XY2.
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The diagram show the box for an element in the periodic table . What is the atomic mass of the element shown .
Answer:32.1
Explanation:
A calibration curve was created to determine the quantity of protein in a solution. The calibration curve has the form of a straight line with the equation A = 0.0182 x +0.007 where A is the corrected absorbance of the solution and x is quantity of protein in the solution in units of micrograms (μg). Determine the quantity of protein in a solution that has an absorbance of 0.207. A blank solution has an absorbance of 0.050 .
Answer:
(a) 10 quantities of protein
(b) 2 quantities of protein
Explanation:
Given
[tex]A = 0.0182 x +0.007[/tex]
Solving (a):
Solve for x when A = 0.207
Substitute 0.207 for A
[tex]A = 0.0182 x +0.007[/tex]
[tex]0.207 = 0.0182x + 0.007[/tex]
Solve for 0.0182x
[tex]0.0182x = 0.207 - 0.007[/tex]
[tex]0.0182x = 0.200[/tex]
Solve for x
[tex]x = 0.200/0.0182[/tex]
[tex]x = 10.989010989[/tex]
[tex]x = 11[/tex] (Approximated)
Solving (b):
Solve for x when A = 0.050
Substitute 0.050 for A
[tex]A = 0.0182 x +0.007[/tex]
[tex]0.050 = 0.0182x + 0.007[/tex]
Solve for 0.0182x
[tex]0.0182x = 0.050 - 0.007[/tex]
[tex]0.0182x = 0.043[/tex]
Solve for x
[tex]x = 0.043/0.0182[/tex]
[tex]x = 2.36263736264[/tex]
[tex]x = 2[/tex] (Approximated)
A woman is brought into the emergency room experiencing nausea and vomiting. She is also hyperventilating. She says that she ingested a bottle of aspirin about two hours earlier. Aspirin (acetylsalicylic acid) is converted to salicylic acid in the stomach. Assuming 100% conversion to salicylic acid.
Required:
Calculate the percentage of protonated and unprotonated forms of salicylic acid in her stomach, given a pH of 2.0 for the stomach.
Answer:
Protonated form: 96.87%
Unprotonated form: 3.13%
Explanation:
To find the percentage of protoned and unprotoned forms of salicylic acid we must use Henderson-Hasselbalch equation:
pH = pKa + log [A⁻] / [HA]
Where pKa of salicylic acid is 3.49; [A⁻] is the unprotonated form and [HA]:
2.0 = 3.49 + log [A⁻] / [HA]
0.03236 = [A⁻] / [HA] (1)
And as:
[A⁻] + [HA] = 100% (2)
Replacing (2) in (1):
0.03236 = 100 - [HA] / [HA]
0.03236 [HA] = 100 - [HA]
1.03236[HA] = 100
[HA] = 96.87%And [A⁻]:
[A⁻] = 100 - 96.87
[A⁻] = 3.13%