Answer:
32.3%
Explanation:
Percent yield is defined as:
Actual yield (125.5g) / Theoretical Yield * 100
To find theoretical yield we have to find the moles of aluminium. As 2 moles of Al produce 2 moles of AlCl3, the moles of Al = Moles AlCl3.
With these moles we can find the mass assuming a 100% of yield (Theoretical Yield) as follows:
Moles Al = Moles AlCl3 (Molar mass Al = 26.98g/mol)
72g Al * (1mol / 26.98g) = 2.67 moles AlCl3
Mass AlCl3 (Molar mass: 133.34g/mol)
2.67 moles AlCl3 * (133.34g / mol) = 355.8g AlCl3
Percent Yield = 125.5g / 355.8g * 100 =
32.3%What is the molality of a solution in which 0.32 moles aluminum chloride has been dissolved in 2,200 g water
4
If a gas takes up 250 ml at 800. torrand 50.°C, how much space will it take up at 400 torr and 25°?
A 125 ml
B 500 ml
0.46 L
D 0.542 L
Answer: The space occupied by the gas at 400 torr and [tex]25^{o}C[/tex] is 250 mL.
Explanation:
Given: [tex]V_{1}[/tex] = 250 mL, [tex]P_{1}[/tex] = 800 torr, [tex]T_{1} = 50^{o}C[/tex]
[tex]V_{2} = ?[/tex], [tex]P_{2}[/tex] = 400 torr, [tex]T_{2} = 25^{o}C[/tex]
Formula used is as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}[/tex]
Substitute the values into above formula as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}\\\frac{800 torr \times 250 mL}{50^{o}C} = \frac{400 torr \times V_{2}}{25^{o}C}\\V_{2} = 250 mL[/tex]
Thus, we can conclude that space occupied by the gas at 400 torr and [tex]25^{o}C[/tex] is 250 mL.
Whch is more acidic, a solution with a pH of 2 or 5
Answer:
A solution with a pH of 2
Explanation:
The lower a pH is in a liquid, the more acidic it is. 7 is the neutral pH for a liquid. We usually drink around that pH for water. A pH higher than 7 expresses that the liquid is a base.
Answer:
A solution with a pH of 2 is more acidic.
Explanation:
The solution with a pH of 2 is more acidic because on the pH scale as you get closer to zero, the more acidic the solution becomes.
2.3g of lithium chloride in 500cm3 of solution
Answer:
0.109M
Explanation:
Find molarity of the solution:
Molarity is defined as the ratio between the moles of the solute (Lithium Chloride in this case) per liter of solution. To solve this question we have to find the moles of LiCl and its volume as follows:
Moles LiCl -Molar mass: 42.394g/mol-
2.3g * (1mol / 42.394g) = 0.0543 moles
Volume in liters:
500cm³ * (1L / 1000cm³) = 0.500L
Molarity:
0.0543 moles / 0.500L =
0.109M
I can't do Miscellaneous calculations!
E.g.
How many moles of oxygen atoms are present in 2.5 mole of water molecules?
what are the effect of water pollition
Is Zinc sulfide ionic or covalent?
Hikers have noticed that a sealed bag of potato chips puffs up when taken to the top of a mountain. Suppose that at the valley floor below, the air pressure is 1.0 atm, temperature is 25°C, and the volume of the chip bag is 0.985 L. At the top of the mountain, the temperature is 22°C and the chip bag has puffed up to 1.030 L.
What is the air pressure on top of the mountain?
__ atm
Answer:
0.95
Explanation:
trust
why an offspring and its parent share many common traits?
Answer:
Explanation: Traits are characteristics, such as its size or height and that comes from parents or other relatives.
Need to finish TODAY ASAP! HIgh point questions
Answer:
The answer is C. The wire is there so that electrons can flow from one electrode to another, because without the wire, there would be nothing connecting them and the electrons would not be able to flow to each of the electrodes.
If 10.5 g of iron, at 25°C, absorbs 128 J of heat, what will be the final temperature of metal? (The specific heat of iron is 0.449 J g-1 °C-1)
Answer:
27.5°C = Final Temperature of the metal
Explanation:
The change in temperature using the specific heat of a material could be obtained using the formula:
Q = m*S*ΔT
Where Q is heat absorbed in Joules = 128J in the problem
m is the mass of the substance = 10.5g
S is Specific Heat of the substance = 0.449J/g°C for Iron
ΔT is change in temperature = Final T - Initial T
Replacing:
128J = 10.5g*0.449J/g°C*ΔT
2.5°C = ΔT
2.5°C = Final T - 25°C
27.5°C = Final Temperature of the metal
calculate the molar mass of hydrogen phosphate
Answer:
95.9793 g/mol
Explanation:
How does the atmospheric pressure at altitudes above sea level compare with atmospheric pressure at sea level?
A. The atmospheric pressure above sea level is higher.
B. The atmospheric pressure at sea level is higher.
c. The pressures are the same.
D. Differences in pressures cannot be determined.
Answer:
Option B
The atmospheric pressure at sea level is higher.
Explanation:
Atmospheric pressure can simply be understood as the weight of the air molecules in the atmosphere. The higher we go up into the atmosphere, the thinner the air becomes. This means that the air present at higher heights is not so much, and hence, the air is lighter. This is why most fighter jets and mountain climbers need oxygen tanks to breathe properly.
Due to the fact that the air is less dense (lighter) at higher altitudes, it also means that the atmospheric pressure at higher altitudes is less.
Therefore, the atmospheric pressure at the sea level is higher than the atmospheric pressure at altitudes above sea level
Answer:
B. The atmospheric pressure at sea level is higher.
Explanation:
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1
Yusef is doing an experiment to find out how the amount of sunlight affects the growth of a seedling. He has three identical pots
containing grass seeds he planted at the same time. He puts them in windows that receive different amounts of sunlight each day.
Every day. Yusef looks at the pots and records his observations. What is the independent variable in Yusef's experiment?
OA type of soil
OB type of seedling
Ос.
amount of water
OD
amount of sunlight
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Next Question
Answer:
asdffafAFSAfdsdf
Explanation:
A substance has a boiling point of 78 °C. Which of the following is true about the substance? (5 points) a It will also change from a gas to a solid at 78 °C while the gas loses energy. b It will also change from a gas to a solid at 78 °C while the gas gains energy. c It will also change from a gas to a liquid at 78 °C while the gas loses energy. d It will also change from a gas to a liquid at 78 °C while the gas gains energy.
Answer: If a substance has a boiling point of [tex]78^{o}C[/tex] then it is true that it will also change from a gas to a liquid at 78 °C while the gas loses energy.
Explanation:
The temperature at which vapor pressure of a liquid substance becomes equal to the atmospheric pressure is called boiling point of substance.
At the boiling point, liquid phase and vapor phase remains in equilibrium.
This means that as liquid phase changes into vapor phase and also vapor phase changes into liquid phase at the boiling point.
Thus, we can conclude that if a substance has a boiling point of [tex]78^{o}C[/tex] then it is true that it will also change from a gas to a liquid at 78 °C while the gas loses energy.
Can u guys help me I have an f in science and this will help me a lot with my grade.
Answer:
First slide:
1) diffusion
2)water
3)high
4)low
5)balance
Second slide:
1)movement
2)without
3)energy
4)high
5)low
6)equilibrium
Final slide:
1)passive
2)energy
3)randomly
4)high
5)low
6)equilibruim
7)permeable
8)Osmosis
9)water
Hopes this helps! Good luck!
Please heeelp to solve these problems
Answer:
Q.89
Alkane - CnH(2n+2)
given that 8 H = > 8= 2n+2
therefore n= 3
C3H8 = 12×3 + 8×1= 36 +8 = 44
5. A sample of an unknown metal has a mass of 120.4 g. As the sample cools from 90.5°C to 25.7°C, it releases 7020. J of energy. What is the specific heat of the sample? Identify the metal among those in the data table below. Finally, is this endothermic or exothermic?
Answer: The specific heat capacity of the sample is [tex]0.899 J/g^{o}C[/tex] and as heat is released in this reaction so it is exothermic in nature.
Explanation:
Given: Mass = 120.4 g
Heat energy released = -7020 J
Initial temperature = [tex]90.5^{o}C[/tex]
Final temperature = [tex]25.7^{o}C[/tex]
Formula used is as follows.
[tex]q = m \times C \times (T_{2} - T_{1})[/tex]
where,
q = heat energy
m = mass of substance
C = specific heat capacity
[tex]T_{1}[/tex] = initial temperature
[tex]T_{2}[/tex] = final temperature
Substitute the values into above formula as follows.
[tex]q = m \times C \times (T_{2} - T_{1})\\-7020 J = 120.4 g \times C \times (90.5 - 25.7)^{o}C\\C = \frac{-7020 J}{120.4 \times (-64.8^{o}C)}\\= \frac{7020 J}{7801.92} J/g^{o}C\\= 0.899 J/g^{o}C[/tex]
When heat is released in a process or reaction then it means it is exothermic in nature.
Thus, we can conclude that the specific heat capacity of the sample is [tex]0.899 J/g^{o}C[/tex] and as heat is released in this reaction so it is exothermic in nature.
What is the ion found in a basic solution?
A. OH +
B. H+
C. OH-
D. H-
answer ASAP plz
pls help it's about density
a railroad car with a mass of 90,000 kg is traveling along a straight, horizontal track at a constant speed of 2 m/s. the car collides with a second railroad car, also with a of 90,000 kg that is initially at rest. The railroad cars stick together after the collision, as shown in the figure.
1) 0.5 m/s
2) 1 m/s
3) 2 m/s
Answer:
I think it's 2.
Explanation:
The weight should transfer half of it's velocity to the other one. or its 1
Why do you think volcanoes are found in a line ?
Answer:
i never seen a volcano before
Which of these elements will successfully create a 1:1 bond with Boron (B)
Phosphorus (P)
Helium (He)
Nitrogen (N)
Aluminum (AI)
Answer:
Option D, Aluminum
Explanation:
Valency of boron and hence it requires three electron to complete its outermost shell.
Valency of Aluminum is also three and it can donate three electrons to boron to complete the outermost shell of itself as well as the boron.
Hence, Aluminum and Boron will form 1:1 bond with each other. (Al-B)
Hence, option D is correct
3. a. How many moles of NaCl are dissolved in 152 mL of a solution if the concentration of the solution is 0.364 M?
Answer:
Good luck man
Explanation:
Good luck man
The type of stem cells that are thought to be pluripotent are found in
A.) embryos
B.) developed tissues
C.) cord blood
D.) the placenta.
Answer:
Embryonic stem cells
Explanation:
Answer:
C.)
Explanation:
( Hope this helps 0_0 )
during prophase a group of fibers called what forms the cell
Answer:
During prophase, the nucleus disappears, spindle fibers form, and DNA condenses into chromosomes ( sister chromatids ). During metaphase, the sister chromatids align along the equator of the cell by attaching their centromeres to the spindle fibers.
Explanation:
I will give the brainliest
The concentration of a saturated solution of calcium carbonate, CaCO3, is 8.7 × 10-9 Molar. What is the Ksp of calcium carbonate?
A.
4.7 × 10-13
B.
9.3 × 10-5
C.
7.6 × 10-17
D.
8.7 × 10-17
Answer:
C
Explanation:
x = 8.70 x 10^-9 M
Ksp = [x][x] = x² = (8.70 x 10^-9)^2 = 7.57 x 10^-17
what does molecule mean?
a.) A pure substance, only one type of atom
b.) Two or more atoms held together by chemical bonds
c.)Composed of two or more separate elements
d.)The smallest part of matter still retaining chemical properties
A pure substance, only one type of atom
Answer:
(a) a pure substance, only one type of atom
Name the following alkene:
CH3CH2CH2CH2CH = CH2
Answer:
1-hexene. is your answer.
The name of the given alkene is Hex-1-ene
In order to name the given alkene, we will follow some of the IUPAC rules for naming alkenes. The rules are:
1. The longest chain chosen for the root name must include both carbon atoms of the double bond.
2.The root chain must be numbered from the end nearest a double bond carbon atom.
3. The smaller of the two numbers designating the carbon atoms of the double bond is used as the double bond locator.
The given alkene is
CH3CH2CH2CH2CH = CH2
The longest chain has 6 carbon atoms, which means it is a Hexene.
If numbered from the end nearest the double bond carbon atom, the double bond will be on carbon - 1
∴ Hex-1-ene
Hence, the name of the given alkene is Hex-1-ene
Learn more on naming organic compounds here: https://brainly.com/question/24328002
What are the 3 most valuable metals in the United States? A. Lead b. Gold c. Iron d.Copper e.Coal f.Silver g.Titanium
Answer:
Gold, Silver and Titanium
Explanation:
The most valuable metals in the list are:
Gold:
Its value makes it a good investment option. Gold can be used in many different ways, like in jewelry, electronics, medicine, etc.
Silver:
Similar to the case of gold, besides the common value of silver in jewelry, it can be also used in other ways, because it has a large thermal and electrical conductivity.
Finally, the titanium: It's price is actually close to the copper one, but for the cost of work with titanium (Titanium has a really large melting point, then melting it into ingots needs a lot of energy), the price of titanium is increased.