Answer:
1. 66.96°C
2. -1776.5J
3. 179.9°C
Explanation:
Using the formula;
Q = m × c × ∆T
Where;
Q = amount of heat (J)
m = mass (g)
c = specific heat capacity (J/g°C)
∆T = change in temperature (°C)
QUESTION 1:
∆T = ?
m = 160g
c = 0.14 J/g°C
Q = 1500 J
1500 = 160 × 0.14 × ∆T
1500 = 22.4∆T
∆T = 1500/22.4
∆T = 66.96°C
QUESTION 2:
Q = ?
m = 85g
c = 0.11 J/g°C
∆T = 10°C - 200°C = -190°C
Q = 85 × 0.11 × -190
Q = -1776.5J
QUESTION 3:
Q = 1404 J
m = 38g
c = 0.24 J/g°C
Final temperature = ?
Initial temperature = 26°C
1404 = 38 × 0.24 × (T2 - 26)
1404 = 9.12 (T2 - 26)
1404 = 9.12T2 - 237.12
9.12T2 = 1404 + 237.12
9.12T2 = 1641.12
T2 = 1641.12 ÷ 9.12
T2 = 179.9°C
Which of the following isotopes have 8 neutrons in the nucleus?
O-15
O-17
C-13
C-14
Answer:
C-14 have 8 neutrons in the nucleus.
Carbon atoms with 8 neutrons have an atomic mass of 14 (6 protons + 8 neutrons = 14), so this isotope of carbon is named carbon-14.
hope it helps :)
Explanation:
Answer:
its d
Explanation:
edge 21
Which of the following is a property of carbon atoms?
They are chemically inert.
They have six valence electrons.
They readily give up two electrons
They are found in all living things.
They are found in all living things. Hence, option D is correct.
What is an atom?An atom is any particle of matter which contains at least one proton.
Carbon is stored in plants and trees. Plants take carbon dioxide from the atmosphere to make the building blocks of food during photosynthesis. Carbon is stored in the hydrosphere and dissolved in ocean water and lakes. Carbon is used by several organisms to produce shells.
Hence, option D is correct.
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When the temperature of the water was 10°C the waterweed did not produce bubbles.
Suzi increased the temperature of the water in the water-bath to 20°C. The waterweed started to produce bubbles.
She waited two minutes before starting to count the bubbles.
Explain why she waited for two minutes before she started to count the bubbles.
Science
Explanation:
she could waited for the saturated vapour pressure to equal the prevailing atmospheric pressure
ergo boiling to take place seeing as she had gotten the first indication that boiling had started
HELP! Calculate the pH of the following solutions:
a) [OH-] = 3.1x10^-8 M
pH = 7.51
pH = 3.18
pH = 8.00
pH = 6.49
pH = 3.10
b) [H3O+] = 5.2x10^-7 M
pH = 7.72
pH = 7.00
pH = 6.28
pH = 5.27
pH = 5.20
c) [OH-] = 5.9x10^-5 M
pH = 5.00
pH = 5.90
pH = 4.23
pH = 5.59
pH = 9.77
d) [OH-] = 5.9x10^-3 M
Answer:
Adding base causes the pH of a solution to increase
pH is a measure of the hydrogen ion concentration of a system. Solutions with a low pH possess a high concentration of hydrogen ions, while solutions with a high pH possess a low concentration of hydrogen ions. To increase the pH of a solution, base can be added to it. Base will release hydroxide ions (OH-) in the solution which will neutralize or reduce the H+ ions concentration in the solution. This way the pH is increased.
Explanation:
If two half lives have passed since a scientist collected a 1.00- gram sample of a U-235, how much U-235 is left now?
answers for most finals chem test questions (10th)
Answer:
one quarter of the original amount, so 0.25 g
Explanation:
Answer:
C
Explanation:
the kinetic theory of matter states that the atoms of a diamond are. | A. Transparent B. Always Moving C. Reflectors of light D. Extremely Hard
Answer:
Always moving!
Explanation:
matter is composed of very small atoms and molecules that are always in contant motion
Which reaction demonstrates bonds breaking?
PC13(g) → P (g) + 3Cl (g)
P(g) + 3 Cl(g)
PC13 (g)
A 35 L tank of oxygen is at 315 K with an internal pressure of 190 atmospheres. How
many moles of gas does the tank contain?
Answer:
600.7 moles
Explanation:
Applying,
PV = nRT................... Equation 1
Where P = Pressure of oxygen, V = Volume of oxygen, n = number of moles, R = molar gas constant, T = Temperature.
make n the subject of the equation
n = PV/RT............... Equation 2
From the question,
Given: P = 190 atm, V = 35 L, T = 135 K
Constant: R = 0.082 atm.dm³/K.mol
Substitute these values into equation 2
n = (190×35)/(135×0.082)
n = 600.7 moles of xygen
BRAINLIEST IF RIGHT!! Write 200.0398 in 2 sig figs.
Answer:
20
step by step explanation:
True or false gases have no mass
Answer:
Gases have mass, because they are made up molecules which have mass
In the given question, the given statement about gases have no mass is false.
The amount of substance in a thing is measured by mass, which is a physical attribute of matter. It is usually expressed in grams (g) or kilograms (kg).
Gases do have mass. The statement is false because gases consist of molecules that have mass.
Various ways can be used to determine the mass of a gas, such as weighing the container in which the gas is contained before and afterwards the gas is supplied. Additionally, the ideal gas law,[tex]\rm PV = nRT[/tex], includes the variable "n" which represents the number of moles of gas, indicating that gases do indeed have mass.Therefore, the given statement is false about gases having no mass.
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Please help, lots of points!
If you were working for a beverage company, which molarity would you recommend, and what directions for mixing would you create for the drink package? Support your claims using the data you collected.
The 1.0 M beverage solution which is mixed by stirring would be the best molarity based on the data collected.
What is a beverage?A beverage is a liquid other than water which is consumed by humans to provide the body with energy and nutrients as well as to quench thirst.
A good quality beverage is sweet, fluid and clear.
From the data in the table, the molarity that meets these criteria is 1.0 M with stirring.
Therefore, I would recommend the 1.0 M beverage solution which is mixed by stirring.
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Please help me ASAP!!!!
Answer:
Explanation:
Determine the balanced chemical equation for the chemical reaction.
Convert all given information into moles (most likely, through the use of molar mass as a conversion factor).
Calculate the mole ratio from the given information.
What is the pressure of gas at 496 Liters and 200 Kelvin if the original pressure was 0.250 atm. at 300 liters and 400 kelvin?
Answer:
0.076 atm
Explanation:
Using the combined gas law formula;
P1V1/T1 = P2V2/T2
Where;
P1 = initial pressure (atm)
P2 = final pressure (atm)
T1 = initial temperature (K)
T2 = final temperature (K)
V1 = initial volume (L)
V2 = final volume (L)
According to the information provided in this question;
P2 = ?
P1 = 0.250 atm
V2 = 496 L
V1 = 300 L
T2 = 200K
T1 = 400K
Using P1V1/T1 = P2V2/T2
0.250 × 300/400 = P2 × 496/200
75/400 = 496 P2/200
0.1875 = 2.48P2
P2 = 0.1875 ÷ 2.48
P2 = 0.076 atm
1.) What is the difference between renewable and nonrenewable resources?
2.) Explain why people need to begin using renewable resources instead of nonrenewable
resources.
Answer: 1.) renewable resources can be replenished as fast as they are used. Nonrenewable resources are unable to be replaced at the same rate at which they are used. 2.) nonrenewable energy sources will eventually run out, leaving people to figure out how to continue running their cars, homes, and busines. They must find alternative sources of energy. Since renewable energy resources that will never run out, it is a great option.
Explanation:
Which is NOT a way to accelerate an object? *
do not disturb it
speed it up
change it’s direction
slow it down
A gas occupies a volume of 60 L at a temperature of 0.5 K. What will the volume be at 4 K?
Answer:
480 L
Explanation:
In order to solve this question, you should be familiar with gas laws. (I will attach a picture showing all of them under my answer.) In this question in particular, however, we only need Charles's Law because we're dealing with temperature and volume.
As we can see, Charles's Law is:
[tex]\frac{V_{1} }{T_{1} } = \frac{V_{2} }{T_{2} }[/tex]
or, initial volume over initial temperature equals final volume over final temperature.
In this question, 60 L is our initial volume, and 0.5 K is our initial temperature (K being Kelvin). We are only given 4 K as our final temperature. We are asked to solve for the final volume. Let's set up the equation and solve for [tex]V_{2}[/tex]:
--------------------------------------------------------------------------------------------------------------
(60) / (0.5) = [tex]V_{2}[/tex] / (4)
↓
120 = [tex]V_{2}[/tex] / 4
×4 ×4
↓
[tex]V_{2}[/tex] = 480 L
--------------------------------------------------------------------------------------------------------------
There's our answer! Feel free to comment if you have any questions about my answer :)
PLEASE HELP NEED ANSWER ASAP!!!!
Use 3 H2(g) + N2(g) <--> 2 NH3 (g) + 92.4 kJ
At equilibrium, if the hydrogen (H2) concentration is increased, the ammonia(NH3) concentration will
Select one:
a. decrease
b. shifts back and forth
c. increase
d. remain the same
Answer:
the correct answer is option A. decrease
Can animals and plants adapt to climate changes?
Answer:
Yes but will take a very very long time for them to adapt most will die but as gemeration passes they will get used to it
You can prepare a buffer solution by combining equal moles of which pair of substances?
A. weak acid and its conjugate base
B. strong acid and a strong base
C. strong base and its conjugate acid
D. salt and a weak acid
Answer:
A. weak acid and its conjugate base
Explanation:
A buffer solution can be made with a weak acid and conjugate base or a weak base and conjugate acid.
This may help you:
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Buffers/Introduction_to_Buffers
Planets X and Y orbit each other in space. Which changes would have the greatest effect on increasing the gravitational attraction between the two planets?
Group of answer choices
Halving the mass of planet X and doubling the distance between the planets
Halving the mass of planet X and halving the distance between the planets
Doubling the mass of planet X and halving the distance between the planets
Doubling the mass of planet X and doubling the distance between the planets
Answer:
halving, the mass of planet X and halving the distance between the planets
The gravitational force of attraction is the fundamental force of the universe. Doubling the mass of planet X and halving the distance between the planets increases the gravitational attraction. The correct option is C.
What is gravitational attraction?The force of attraction between any two bodies is directly proportional to the product of their masses and is inversely proportional to the square of the distance between them. The formula of gravitational force is given as:
F = G m₁m₂ / r²
From the equation it is clear that the gravitational force increases with the increase in the mass and decreases with the increase in the distance between the objects. This law is true for each particle of matter, each particle of matter attracts every other particles.
Here doubling the mass of planet X and halving the distance between the planets increases the gravitational attractive force.
Thus the correct option is C.
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What does all matter have in common?
A.
It is made up of atoms.
B.
It is made up of molecules.
C.
It is all solid.
D.
It is too small to see.
If it requires 75.0mL of 0.500M NaOH to neutralize 165.0 mL of an hcl solution what is the concentration of the hcl solution
Answer:
0.027 M HCl
Explanation:
The chemical equation of the neutralization is:
1 NaOH + 1 HCl -> 1 H2O + 1 NaCl
Because the ratio of NaOH and HCl is 1:1 you can use the M1V1=M2V2 formula.
(75 mL)(0.5 M NaOH) = (165 mL)(M HCl)
It requires 0.027 M HCl.
A gas diffuses 1/6 times faster than hydrogen gas (H2).
What is the molar mass of the gas? (5 points)
a
59.95 g/mol
b
66.54 g/mol
c
68.68 g/mol
d
72.58 g/mol
Answer:
72.58 g/mol
Explanation:
mark me brainless if I am ✅
The relationship between the rate of diffusion and the molar mass is given by Graham's law. A gas diffusing 1/6 times faster than hydrogen will have a molar mass of 72.58 g/mol. Thus, option d is correct.
What is Graham's law?Graham's law states the inverse relationship between the rate of diffusion and the square root of the molar mass of the gas. It is given as,
Rate = 1 ÷ √M
The molar mass of the gas that diffuses 1/6 times faster than hydrogen is calculated as,
R₁ ÷ R₂ = √ (M₂ ÷ M₁)
Here,
The molar mass of hydrogen = M₁
The molar mass of unknown gas = M₂
Rate of diffusion of hydrogen gas = R₁
Rate of diffusion of unknown gas = R₂ = 1 / 6 R₁
Substituting values:
R₁ ÷ 1/6 R₁ = √M₂ ÷ 2
6 × 1.414
= 8.485
= 84.85 g/mol ≈ 72.58 g/mol
Therefore, option d. 72.58 g/mol is the molar mass of unkown gas.
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Answer is C
Zeke is attempting to react a piece of magnesium metal with sulfuric acid. The sulfuric acid is a 5M solution. What could Zeke do
to slow down the rate at which the magnesium will react with the acid?
A)
increase the temperature
B)
add a 10M sulfuric acid solution
9)
add water to the acid to decrease its molarity
D)
add more of the 5M sulfuric acid to the reaction
Answer:
c)
Explanation:
add water to the acid to decrease its molarity
Please show your work if possible!
Answer:
54.93 g/mol
Explanation:
a) the element with symbol Mn is known as Manganese and I figured it out by looking at the periodic table.
b) I took a look at the periodic table again, and seen how much the atomic mass is and from there I observed:
Mn= 54.938 g/mol
rounded is 54.94 g/mol
A Chemist reacted magnesium and aluminum oxide. A reaction takes place. Explain why
Explanation:
when Magnesium is reacted with Aluminum oxide, Aluminum being a less reactive metal than magnesium, is replaced by magnesium
Al2O3 + 3Mg - 3MgO + 2Al
hence reaction takes place
Prokaryotic and eukaryotic cells have many different characteristics. One difference
between prokaryotic and eukaryotic cells is that all eukaryotic cells —
Answer:
Have a nucleus
Explanation:
Pls check..
Review the equation below.
2KClO3 Right arrow. 2KCl + 3O2
How many moles of oxygen are produced when 2 mol of potassium chlorate (KClO3) decompose?
2KClO3 --> 2KCl + 3O2
3 moles of oxygen are produced when 2 mol of potassium chlorate (KClO3) decompose.
Answer:
The answer is 3
Explanation:
I did the test on Edge
The picture below shows brown bears by the side of a river.
In this environment, the brown bears by the river are
Answer:
being peaceful
and washing up
Anyone know this question