Answer:
1.806 x 10^24 atoms total
Explanation:
How is coal extracted?
How do Humans use it?
What are the benefits?
Coal is extracted by mining.
Once coal has been extracted, it can be used directly for heating and industrial processes or to fuel power plants for electricity.
Benefits are:
Coal energy is an affordable energy source because of the coal's stable price compared to other fuel sources.
Coal is easy to burn.
Coal produces high energy upon combustion.
Coal energy is inexpensive.
What percentage of a substance remains after 7 half-lives have passed?
A. 0.39
B. 2.5
C. 1.25
D. 0.78
Answer:
Not really sure, buts its either B or C.
A solute dissolved in water will cause
A the boiling point to increase
B the freezing point to increase
C the melting point to increase
D the boling point to decrease
(It’s A)
Answer:
A the boiling point to increase
Explanation:
That is a colligative property
Calculate how many grams of sodium chloride we would need to make a solution with the same molarity of seawater, which is about 0.598 M.
Answer:
34.92 grams NaCl (in 1 L of solution)
Explanation:
The chemical formula of sodium chloride is NaCl. From the formula, we can calculate the molar mass of NaCl:
MM(NaCl)= MM(Na) + MM(Cl) = 23 g/mol + 35.4 g/mol = 58.4 g/mol
A solution of NaCl with a molarity of 0.598 M has 0.598 moles of NaCl per liter of solution. So, we multiply the moles by the molar mass of NaCl to calculate the mass we need:
mass of NaCl = 0.598 mol x 58.4 g/mol = 34.92 g NaCl
Therefore, we need 34.92 grams of NaCl to prepare 1 liter of a solution with a molarity of 0.598 M.
URGENT!!!
Which statement explains why an increase in molality increases the boiling point of a solution? The addition of solute decreases the solvent’s vapor pressure. A higher temperature must then be applied to overcome the change. The addition of solute increases the solvent’s vapor pressure. A higher temperature must then be applied to overcome the change. The addition of solute increases the solvent’s ability to boil. The solute’s molecules repel the solvent’s molecules, giving them higher binding energy and hence the need for higher temperature.
Answer:
the addition to solute decreases the solvent's vapor pressure. a temperature must then be applied to overcome the change
Explanation:
Answer:
long story short: A
Explanation:
The rate constant for a first order reaction
is 2.80-10-35-1 at 60.0°C. The rate
constant at 45.0°C is 4.80.10-4 5-1. What
is the activation energy for the reaction?
[ ? ]kJ/mol
Recall that R = 8.314 J/mol K
Answer:
E_a = 103.626 × 10³ KJ/mol
Explanation:
Formula to solve this is given by;
Log(k2/k1) = (E_a/2.303R)((1/T1) - (1/T2))
Where;
k2 is rate constant at second temperature
k1 is rate constant at first temperature
R is universal gas constant
T1 is first temperature
T2 is second temperature
We are given;
k1 = 2.8 × 10^(-3) /s
k2 = 4.8 × 10^(-4) /s
R = 8.314 J/mol.k
T1 = 60°C = 333.15 K
T2 = 45°C = 318.15 K
Thus;
Log((4.8 × 10^(-4))/(2.8 × 10^(-3))) = (E_a/(2.303 × 8.314))((1/333.15) - (1/318.15))
We now have;
-0.76592 = -0.00000739121E_a
E_a = -0.76592/-0.00000739121
E_a = 103.626 × 10³ KJ/mol
10) Which preparation produces a 2.0 M solution of Co
H1206? [molecular mass = 180.0]
(A) 180.0 g of C6H12O6 dissolved in 1000. mL of
solution
(B) 90.0 g of C6H1206 dissolved in 1000. mL of
solution
(C) 180.0 g of C6H1206 dissolved in 500.0 mL of
solution
(D) 90.0 g of C6H1206 dissolved in 500.0 mL of
solution
Answer:
(C) 180.0 g of C6H12O6 dissolved in 500.0 mL of solution
Explanation:
Molarity is mole/volume.
1. Find the mass of C6H12O6 in 1 Liter of 2.0 solution
(2 mol C6H12O6 / L) * (180 g / mol C6H12O6) = 360 g C6H12O6
There are 360 g C6H12O6 in 1000 mL of solution
2. Compare the value you found in step 1 to each of the multiple choice answers.
180.0 g of C6H12O6 dissolved in 500.0 mL of solution is exactly proportional to 360 g C6H12O6 in 1000 mL of solution.
The preparation which produces a 2.0 M solution of C₆H₁₂O₆ is 180.0 g of C₆H₁₂O₆ dissolved in 500.0 mL of solution.
How molarity is calculated?Molarity is defined as the number of moles of solute present in per liter of solution.
Moles of any substance will be calculated as :
n = W/M, where
W = given mass
M = molar mass
In the question given that molar mass of C₆H₁₂O₆ is 180 g/mole, and let we have produced the solution of 2 molarity by these amount in 1 liter i.e.
2 = n/1
n = 2 moles
Now by using these moles we can calculate the required mass of C₆H₁₂O₆ as:
2 = W/180
W = 360g
From this it is clear that for the preparation of 1 liter of solution of 2 molarity 360g of C₆H₁₂O₆ is required. So in 500mL of solution, 180 g of C₆H₁₂O₆ will use.
Hence, option (C) is correct i.e. 180.0 g of C₆H₁₂O₆ dissolved in 500.0 mL of solution.
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Somebody please help this is due in 30 minutes! (picture is attached)
44.5 g Al2(SO4)3
Explanation:
# moles Ba(NO3)2 = (0.543M)(0.717 L)
= 0.389 mol Ba(NO3)2
Now we use the molar ratios,
0.389 mol Ba(NO3)2 ×(1 mol Al2(SO4)3/3 mol Ba(NO3)2)
= 0.130 mol Al2(SO4)3
0.130 mol Al2(SO4)3 × (342.15 g Al2(SO4)3/(1 mol Al2(SO4)3)
= 44.5 g Al2(SO4)3
Methane, a highly flammable gas, is placed in a piston that has a volume of 2.1
L at STP. The piston then compresses the gas to 125 mL. What is the pressure
inside of the piston?
A solution with a pOH of 4.3 has a [H+] of ??
please help
Answer:
A solution with a pOH of 4.3 has a [H+] of 2*10⁻¹⁰ M.
Explanation:
The pOH (or potential OH) is a measure of the basicity or alkalinity of a solution.
pOH indicates the concentration of hydroxyl ions [OH-] present in a solution. It is defined as the negative logarithm of the activity of hydroxide ions. That is, the concentration of OH- ions:
pOH= -log [OH-]
On the other hand, pH is also a measure of the basicity or alkalinity of a solution. POH is an indicator that is related to pH by:
pOH + pH= 14
So, if the solution has a pOH equal to 4.3, the pH is calculated by:
4.3 + pH= 14
pH= 14 - 4.3
pH= 9.7
The pH is defined as the logarithm of the concentration of H+ ions, with the sign changed:
pH= -log [H+]
So, in this case:
9.7= - log[H+]
Solving
[H+]= 2*10⁻¹⁰ M
A solution with a pOH of 4.3 has a [H+] of 2*10⁻¹⁰ M.
Structures and Forces - What is force and external forces.
Question 1) Jacob and Ravleen are moving furniture. They need to move the filing cabinet over 6 feet and it is very heavy. Jacob wants to apply force and push it by putting his hands on point A because he thinks it would be easier to move it from the top as there is less weight on the top. Ravleen says it's better to push at point B because the center of gravity is lower. Which person is correct and EXPLAIN why and what may happen if it is pushed in the wrong spot.
Answer:
The restoring force that prevents the furniture from tipping over when pushing the furniture towards the right, F= W × D
Where;
W = The weight of the furniture
D = The horizontal distance from the center of gravity of the furniture, CG and the to the lower right corner of the furniture
Given that A > D, for the furniture to tip over when pushing above the CG, we have;
F1 × A ≤ W × D
∴ F1 << W or for a force much smaller than W, the weight of the furniture applied above the center of gravity, the furniture will tip over
However when the force F2 is applied, where C < D, we have for no tipping over;
F2 × C ≤ W × D, therefore, given that C < D, when a force much higher than the weight, W, is applied at F2, the furniture will remain upright
Therefore, it is better push at a point lower than or equal to the center of gravity, whereby the point B is lower than the center of gravity, it is better to push at point B, Ravleen is correct and it is better to push at point B because the center of gravity is lower
If the furniture is pushed at the wrong spot it may tip over
Please see attached drawing
Explanation:
Convert 22 grams of copper Il chloride (Cucl2) to moles.
with work please
For which substance is the standard heat of formation not equal to zero?
Hydrogen (H2)
Aluminum oxide (Al2O3)
Oxygen (O2)
Potassium (K)
Answer:
Aluminum oxide (Al₂O₃)
Explanation:
The standard heat (or enthalpy) of formation of a compound, is the amount of change in the enthalpy that takes place when 1 mole of the compound is produced from the elements it contains whereby the compounds and elements in the reaction are in their standard states
The standard state of an element, is the state in which the element is in the most stable form at a pressure of 1 bar
Therefore, the heat of formation of hydrogen, H₂, oxygen, O₂, and potassium, (K), will have a heat of formation of zero, while Al₂O₃ which is made of aluminum and oxygen in combining to form a compound in proportions which are different from their initial standard states will have a heat of formation not equal to zero
The concentration of a potassium manganate(VII) solution (KMnO4) is 10 g /l . What is the concentration of this solution in molarity?
Answer:
Have anyone found the answer to this? I’m on this grade result course right now
Explanation:
The concentration of a potassium manganate(VII) solution (KMnO4) is 10 g /L. What is the concentration of this solution in molarity is 0.06 M.
What is the molarity?The ratio of number of moles of solute to the volume of the solution in litre is called molarity. it is denoted by symbol M.
Given concentration (C) of potassium manganate(VII) solution in g/L is 10 g /L
Molarity = C/molar mass of KMnO4 = 10g/L ÷ 158.02g/mol = 0.06 mol/L
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Describe how plants and animals may change their characteristics in order to adapt to changes in their environment
please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
One way an animal may adapt to the environment and change characteristics is for example lizards. Lizards are preyed on by birds and other small mammmals. To avoid this some lizards have adapted to color changes or camofaluge.
Explanation:
Answer:
take a octopus for example, they change thw color of their skin to match their environment to stay hidden.
Explanation:
or take a decomposing plant for example, they mimik the process of decomposing to draw animals away
Which is the correct chemical formula for Pentacarbon Tetraphosphide
Answer:
C5P4
Explanation:
the answer is C5P4 because penta is 5 and tetra is 4
You come across two unknown plants and compare their leaves. Plant A has feather like leaves, while Plant B has needles. What type of plant is Plant B? Fern Flowering plant Pine tree Spores
Answer:
The correct answer is - Pine tree.
Explanation:
Coniferous trees or cone-bearing trees normally called conifers adapted their leaves and have needles like leaves that retain more water. Needles do not appear to be leaves but are modified leaves.
Conifer trees adapt this leaf modification to prevent water loss due to transpiration in the case of dry air or atmosphere. Important members of the conifer trees are pine trees, cedars, spruces, and Pines.
The potential energy diagram for a reaction starts at 180 kJ and ends at 300 kJ. What type of reaction does the diagram best represent? (5 points)
Exothermic reaction
Endothermic reaction
Reaction between two solids
Reaction between two liquids
Answer:
Exothermic reaction
Explanation:
An exothermic process releases heat, causing the temperature of the immediate surroundings to rise
The potential energy diagram for a reaction starts at 180 kJ and ends at 300 kJ. the type of reaction does the diagram best represent exothermic reaction.
What is exothermic reaction?An exothermic reaction would be one in which heat energy is emitted. Exo stands for "evolve out." The term "thermos" refers to a container that holds heat. The term "exothermic" refers to a process in which heat is produced. In general, an exothermic reaction is one in which heat is released as a byproduct.
Therefore, the reaction diagram will represent exothermic reaction.
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Two reasons that a plant from a rain forest would not survive in a desert home?
Answer: A planet from a rain forest would not survive in a desert home, for the fact they depend on water and as these live from water, without it, this leads to dehydration and with loss of water with plants, nothing is able to survive when it comes to a rain forest plant being in a desert home. Another reason is the high trees and leaves that are providing the plants enough sunlight or shade to grow, it guarantees to help keep the temperature normal. Being in a deserted area would mean that there would be a temperature change, something the plant is not used to. Without that needed shade and avoiding the scorching sun, they will die out from how different the temperature is, and how hot it is.
Explanation: I hope this helped you.
okay, the answer should be simple and easy, plants from a rainforest would not survive in a desert because the plants in the rainforest do get water, sunlight and air whereas the plants in the desert have Sunlight which is very hot. so if a plant in the rainforest was transferred to the desert it will hard to survive and it will eventually die because they will not get water that will be needed and the plant can get sunburns with the too hot temperature.
What is the difference between Mitosis and Meiosis?
Calculate the molarity of a solution that contains 0.75 moles of lithium fluoride, LiF, in a 65 mL solution.
The molarity (M) of a solution is 11.5 M that contains 0.75 moles of lithium fluoride, LiF in a 65 ml of solution.
What is Molarity ?Molarity (M) is defined as the number of moles of solute dissolved in 1L of solution. Molarity is also known as Molar concentration. The S.I Unit of Molarity is molar (M) or mol/L.
How to find molarity of a solution ?Molarity (M) = [tex]\frac{\text{Number of moles of solute}}{\text{Volume of solution (in liters)}}[/tex]
From the above definition it is clear that the volume of solution is in liter. In question the volume of solution is given in ml.
So, convert 65 ml into l.
65 ml = [tex]\frac{65}{1000}[/tex] = 0.065 l
Now, put the values in above formula, we get that
(M) = [tex]\frac{0.75}{0.065}[/tex] = 11.5 M
Thus, the molarity of a solution is 11.5 M that contains 0.75 moles of lithium fluoride, LiF in a 65 ml of solution.
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The process by which particles in a solution spread out evenly is called?
Answer:
this is your answer.....
What is the number of moles in a sample of gas that has a volume of 3.5 L, a
pressure of 200 kPa, and a temperature of 300 K?
Explanation:
[tex]PV = nRT \\ (200000 \times 3.5 \times {10}^{ - 6} ) = n \times 8.314 \times 300 \\ n = \frac{0.07}{2494.2 } \\ n = 2.81 \times {10}^{ - 5} [/tex]
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What is the radius of this circle if the circumference is 18 pi cm?
Answer: 2.86 inches
Explanation: To find the radius, then, we insert 18 in for the circumference. So 18=2∏r. Solving for r gives 9/∏, or approximately 2.86 inches.
Answer:
2.86 inches
Explanation:
Agustina was standing on the edge of a cliff of unknown height holding a bowling ball. She wanted to find the height of the cliff. She worked with Maite to time the how long the bowling took to fall to the bottom of the cliff. Maite timed the drop at 9.4 seconds on each of their 10 trials. The bowling ball started at rest on each of the trials. What distance did the bowling ball fall in each trial?
Answer:
433 m
Explanation:
Since the fall represents motion under gravity, we use the equation
s = ut - 1/2gt² where s = height of cliff or distance bowling ball falls through, u = initial velocity of bowling ball = 0 m/s(since it starts from rest), t = time = 9.4 s and g = acceleration due to gravity = -9.8 m/s².
So, substituting the values of the variables into the equation, we have
s = 0 m/s × 9.4 s - 1/2 × 9.8 m/s² × (9.4 s)²
s = 0 m - 1/2 × -9.8 m/s² × 88.36 s²
s = 1/2(865.928 m)
s = 432.964
s ≅ 433 m
Arrange ionic compounds in order of decreasing amount of energy released in lattice formation .NaF,MgS,TLN and
The question is incomplete, the complete question is;
Arrange the following ionic compounds in order of decreasing amount of energy released in lattice formation: NaF, MgS, TlN, and CsI.
Answer:
TlN> MgS > NaF > CsI
Explanation:
Recall that lattice energy is the energy evolved when a crystal lattice is formed from its component ions.
The lattice energy depends on the size of the ions. The smaller the sizes of the ions, the larger the lattice energy.
The order of energy released in lattice formation for these compounds is;
TlN> MgS > NaF > CsI
What is the minimum amount of material that must be present in a living organism?
Answer:
Living things can have a minimum of one cell
Explanation:
Living things can have a minimum of one cell; these are called unicellular organisms. Some examples of unicellular organisms: bacteria, algae (plants), some fungi, and protozoa
hope this helps!
In an ecosystem ,cell is the minimum amount of material that must be present in a living organism.
What is an ecosystem?Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.
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Determine the percent composition of Lithium in Li3PO3 (lower case BOTH 3)
Your answer:
A. 20.866%
B. 31.037%
C. 48.097%
D. 10.080%
Answer:
A. 20.866%
Explanation:
First, we calculate molar mass of Li3PO3
Molar mass of Li3PO3 = 6.9 (3) + 31 + 16(3)
= 20.7 + 31 + 48
= 99.7g/mol
To calculate the percent composition of Lithium, we say:
Mass of lithium in compound/mass of compound × 100
% composition = 20.7/99.7 × 100
= 0.208 × 100
= 20.8%.
Need help on this question asap pleasee
Answer:
9.0 moles of CaO
Explanation:
We have the reaction equation as follows;
Fe2O3 + Ca3(PO4)2 -------> 2FePO4 + 3CaO
Now we know from the equation that;
1 mole of iron III oxide yields 3 moles of CaO
Therefore;
3 moles of iron III oxide yields 3 * 3/1
= 9.0 moles of CaO
how refrigerator magnets work
Answer:
Explanation:
Fridge magnets are made of weakly ferromagnetic ceramics like barium ferrite or strontium ferrite. The magnetic field created by the fridge magnet aligns the spins of unpaired electrons in metal atoms in the fridge in such a way that the magnet and the fridge door are attracted to each other; this force keeps the magnet stuck to the fridge.
Answer:
the fridge is a magnet
Explanation:
magnets connect to fridge