Answer:
B) translucent
Explanation:
Light only partially passes through them.
I AM GIVING BRAINLIEST PLEASEE HELPPPP I NEED HELPPPPPP PLEAEEEEEE
63.2 g of BaCl 2 are dissolved in enough water to make a 634 mL solution. What is the molarity?
Answer:
0.479 M or mol/L
Explanation:
So Molarity is moles/litres of solution...often written as M=mol/L
So here we are given grams of BaCl2 which we have to convert to moles. To convert to moles of BaCl2 we have to divide 63.2 g BaCl2 by molar mass of BaCl2 which is 208.23 g/mol so you get 63.2/208.23 = 0.3035 moles of BaCl2
Second step is converting the 634mL to litres by simply dividing by 1000 because we know 1 litre has 1000ml so 634/1000 = 0.634L
Now we just plug these guys in our molarity formula M=mol/L
M= 0.3035/0.634 = 0.479 M or mol/L
Answer:
Interestingly enough, I'm not getting
0.0341% w/v
either. Here's why.
Start by calculating the percent composition of chlorine,
Cl
, in calcium chloride, This will help you calculate the mass of chloride anions,
Cl
−
, present in your sample.
To do that, use the molar mass of calcium chloride, the molar mass of elemental chlorine, and the fact that
1
mole of calcium chloride contains
2
moles of chlorine atoms.
2
×
35.453
g mol
−
1
110.98
g mol
−
1
⋅
100
%
=
63.89% Cl
This means that for every
100 g
of calcium chloride, you get
63.89 g
of chlorine.
As you know, the mass of an ion is approximately equal to the mass of the neutral atom, so you can say that for every
100 g
of calcium chloride, you get
63.89 g
of chloride anions,
Cl
−
.
This implies that your sample contains
0.543
g CaCl
2
⋅
63.89 g Cl
−
100
g CaCl
2
=
0.3469 g Cl
−
Now, in order to find the mass by volume percent concentration of chloride anions in the resulting solution, you must determine the mass of chloride anions present in
100 mL
of this solution.
Since you know that
500 mL
of solution contain
0.3469 g
of chloride anions, you can say that
100 mL
of solution will contain
100
mL solution
⋅
0.3469 g Cl
−
500
mL solution
=
0.06938 g Cl
−
Therefore, you can say that the mass by volume percent concentration of chloride anions will be
% m/v = 0.069% Cl
−
−−−−−−−−−−−−−−−−−−−
I'll leave the answer rounded to two sig figs, but keep in mind that you have one significant figure for the volume of the solution.
.
Explanation:
Which of these Electromagnetic waves has the most kinetic energy and can be
dangerous?
O radio waves
O gamma rays
O ultraviolet waves
O visible light
Answer:
Gamma Rays.
Explanation:
Gamma-ray photons have the highest energy in the EMR spectrum and their waves have the shortest wavelength.
What is the mole fraction of Ba(OH)2 in an aqueous solution that contains 22.8% Ba(OH)2 by mass?
Answer:
0.03
Explanation:
22.8 g Ba(OH)2 (1 mol Ba (OH)2/ 171.34 g) = 0.133 mol Ba (OH)2
77.2 g H2O (1 mol H2O/18 g) = 4.29 mol H2O
X= molar fraction= mol Ba(OH)2/ mol total
X= 0.133/ (0.133+4.29) = 0.03
0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.
What is a mole fraction?The ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all of the components.
Moles of [tex]Ba(OH)_2[/tex]
Moles = [tex]\frac{mass}{molar \;mass}[/tex]
Moles = [tex]\frac{22.8 g Ba(OH)_2}{171.34 g}[/tex]
= 0.133 mol [tex]Ba (OH)_2[/tex]
Moles of [tex]H_2O[/tex]
[tex]Moles = \frac{mass}{molar \;mass}[/tex]
[tex]Moles = \frac{77.2 g H_2O}{18 g}[/tex]
= 4.29 mol [tex]H_2O[/tex]
The mole fraction of [tex]Ba(OH)_2[/tex]
[tex]\frac{mol Ba(OH)_2}{total \;mol}[/tex]
= 0.03
0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.
Learn more about the mole fraction here:
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Why did the United States government set aside land for the first national parks?
A.
They wanted to settle the west as quickly as possible.
B.
They worried people would destroy the animals and land.
C.
They worried Native Americans wouldn’t have anywhere to go.
D.
They wanted to make sure all citizens would get a piece of land.
Answer:
b
Explanation:
hope it helps
Is the equation Zn+HCl > ZnCL2+H2 unbalanced or balanced
Answer:
unbalanced
Explanation:
Cl and H have an extra atom
- Hope that helps! Please let me know if you need further explanation.
What slows down heat energy from escaping the Earth?
Answer:
Greenhouse gases such as carbon dioxide and water vapor make an atmosphere around the earth and make less heat escape
Explanation:
The process by which complex compounds are broken down by enzymes and by which many organic alcohols are formed is called
Answer:
fermentation
Explanation:
How can the motion of atoms in the solid state of most substances be described?
Answer:
The molecules in a solid are stuck in a specific structure or arrangement of atoms. The atoms still vibrate and the electrons fly around in their orbitals, but the entire atom will not change its position.
Brandon is trying to remember how the physical and chemical properties of metals, nonmetals, and metalloids compare. He wrote some notes down, then looked in his textbook to see which notes were correct.
Which of Brandon's notes, listed below, are correct?
I. Metals are the best at conducting heat, and nonmetals are the worst.
II. Metals are the worst at conducting electricity, and nonmetals are the best.
III. The shape of nonmetals is easy to change, but the shape of metals or metalloids is difficult to change.
IV. Nonmetals are dull in appearance while metals are usually shiny.
V. Metals tend to have a high density, and nonmetals tend to have a low density.
Answer:
The correct ones are:
|
|||
|V
V
Explanation:
Answer:
1 for and 5
Ex
Study island
What is the primary role of the United States Bureau of Counterterrorism?
о
to plan counterterrorist attacks
to create active counterterrorism groups
to encourage domestic counterterrorism activities
to advance counterterrorism efforts in other countries
o advance counterterrorism efforts in other countries
Answer:
D
Explanation:
E2020
what is an example of a strong base?
HCl
NaCl
NaOH
HF
Answer:
The answer is NaOH
Explanation:
Strong bases are characterized by the fact that they dissociate completely in an aqueous solution. In this case, sodium hydroxide, NaOH, is classified as a strong base because it dissociates completely in an aqueous solution to form sodium cations, Na+, and hydroxide anions, OH−. Also, it is strong because it totally breaks in its ion. And the base which breaks totally in its atom called the strong base and which doesn't it that is a weak base.
Answer:
NaOH
Explanation:
Got it right in the test. Please mark as brainliest
How many joules are produced when 45 gram of copper is placed into water that releases them temperature from 12c to 71c (c)=0.75j/g*c
Answer:
Heat energy (Q) = 1.9925 KJ = 2 KJ (Approx)
Explanation:
Given:
Mass of copper (M) = 45 gram
Change in temperature (ΔT) = 71°C - 12°C = 59°C
Specific heat (c) =0.75 j /g*c
Find:
Heat energy (Q) = ?
Computation:
Heat energy (Q) = Mass(M) × Change in temperature (ΔT) × Specific heat (c)
Heat energy (Q) = 45 gram × 59°C × 0.75 j /g*c
Heat energy (Q) = 1991.25 J
Heat energy (Q) = 1.9925 KJ = 2 KJ (Approx)
Which statement best describes liquid water and water vapor at equilibrium?
A. Liquid water stops entering the gas phase.
O B. The concentration of liquid water equals the concentration of
water vapor.
C. The concentrations of liquid water and water vapor are stable.
D. The concentration of liquid water is zero.
C. The concentrations of liquid water and water vapor are stable. it describes the fact that liquid water and water vapor are at equilibrium.
EquilibriumAn equilibrium is achieved when no more water vapor can enter into the gas phase from the liquid water during evaporation process. This happens when a saturation is attained between liquid water and the vapor phase.Hence, option (c) is correct. The concentration of liquid water and water vapor will become stable.
Learn more about water vapor:
https://brainly.com/question/17259832
what happens to the density of a box full of leaves if you crush up all the leaves and place them in another box
A the density increases
B the density stays the same
C the density decreases
D the density first decreases, then increases
Answer:
B the density stays the same
A typical cell phone uses wavelength of 0.36meters. How much energy does this wave have?
Answer:
55×10^-26 J
Explanation:
We can calculate the energy of the wave from
E= hc/λ
Where
h= Planks constant = 6.6×10^-34 Is
c= speed of light = 3×10^8 ms-1
λ= wavelength of the wave = 0.36 metres
Recall that cell phone use radio waves which belong to the electromagnetic spectrum hence it must possess the speed of light.
E= 6.6×10^-34 × 3×10^8/ 0.36
E= 55×10^-26 J
Hence the energy possessed by 0.36 meters wavelength radio waves is 55×10^-26 J
What improvements have been made in modern farming? Select all that apply.
1. machines can do more work over less time
2. better seeds sprout and grow much more quickly
3. trains can transport food over long distances faster
4. trains can transport the machines to rural farms once built
5. insecticides used to keep insects off the crops
Answer:
all of them except number 2
Explanation:
Answer:
1,3,4,5 the other perosn is correct
Explanation: That what my quiz said
How are electrons similar and different to the planet Earth?
Answer:
The planets themselves are composed of several trillions or quadrillions or more atoms. As far as hard science is concerned, it would be really hard to picture them as electrons. Conclusion: It can be said with a great accuracy that our planets are NOT huge electrons.
Rutherford's experiments showed that the mass of atoms was mostly concentrated in a very small region, with charge equal to the atomic number- the nucleus. He absolutely did not show, nor is it true, that electrons orbit the nucleus as if they were planets. That was a guess people made in trying to figure out how to picture the atom.
(Hope this helps) Sky
how many Atoms of chlorine Cl are there in 3.45 mol Cl?
Answer:
2.078x10^24
Explanation:
No. of atoms of chlorine = 3.45 x 6.022x 10 ^23 x 1
= 2.078x10^24
( to find no. of atoms of, heres the formula i was taught No. of atoms = no. of moles x Avogadros constant x no. of atoms in the formula of compound)
aight imma let you guys i
Answer:
b
Explanation:
it is right
Why is soap mixed with water?
O A. The soap turns the water molecules into a nonpolar solvent.
B. It covalently bonds to the water so it can be washed away.
O C. Its polar end mixes with the water so it can be washed away.
D. The soap becomes chemically active when mixed with water.
Answer:
Explanation:
Soap breaks up the oil into smaller drops, which can mix with the water. It works because soap is made up of molecules with two very different ends. One end of soap molecules love water - they are hydrophilic. The other end of soap molecues hate water - they are hydrophobic.
Answer:
C. Its polar end mixes with the water so it can be washed away.
Explanation:
Just took test
Where do diamonds come from?
Answer: Diamonds were first discovered and mined in India over 2,400 years ago.
Explanation: Over time, diamonds were found in many other areas around the world, including many in Africa. In today's trade, Africa, Russia, Australia, and Canada produce the most diamonds.
~Wonderopolis
Answer:
Diamonds are formed when under the heat and pressure of the earth's gravity. Diamonds have to be underground to be formed so they should be underground. Digging to Y11 is deep enough to find diamonds .
Which of the following presents a safety hazard while working in the science laboratory?
A knowing how to use equipment
B wearing safety goggles
C following directions
D working alone
Answer:
D working alone
Explanation:
Working alone is the only option that could potentially be a safety hazard; if you have no one watching your back, errors could occur, like dropping glass or burning your hand, and no one is around to help you.
Choices A, B, and C are not correct because those are all good safety standards.
Which sentence best describes part of the process for generating electricity in a nuclear power plant?
A.Atoms Join together to produce water molecules.
B.An atom releases electrons, producing an electric current.
C.Protons and neutrons Join together to create atoms.
D.Heat is released when atomic nuclel split.
Answer:it is D
Explanation: it is only one that makes sense
PLZ HELP OR WILL FAIL!!
Label A drop downs are: condensation, melting, sublimation
Label B drop downs are: condensation, melting, sublimation
Label C drop downs are: condensation, melting, sublimation
What does X represent for this transmutation?
96242Cm + X→ 98245Cf + 01n
gamma
+10e
24He
−10e
Answer:
24He
Explanation:
When a nuclide is bombarded with alpha particles, we notice an increase in its mass and charge since an alpha particle has a mass of four and a charge of +2. recall that nuclear equations must be balanced. That is, the masses and charges on the left hand six and the right hand side of the nuclear reaction equation must be exactly the same.
Looking at the nuclear reaction at hand, the total mass on the left hand side has to be 246 while the total charge on the left hand side of the equation will be 98. Coming over to the right hand side, the total masses are also found to be the same as a neutron with no charge and a mass of 1 is produced. Hence the nuclear reaction equation is balanced when an alpha particle (helium nucleus) is substituted for X in the equation.
Answer:
24HE
I took the test!
Which equilibrium describes a reversible reaction a short time after starting the reaction with reactants only?
Answer:
Should be A
Explanation:
Need help with these three pls!!!!!
Help me!
what is the biggest disadvantage of using nuclear power to produce electricity?
a. nuclear fission releases more air pollution than burning coal
b. nuclear fission produces less energy than burning coal or oil.
c. nuclear waste must be safely stored for many years
d. nuclear waste must be incinerated
The biggest disadvantage of using nuclear power to produce electricity is the nuclear waste must be safely stored for many years.
What is nuclear power?Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from:
Nuclear fission Nuclear decay and Nuclear fusion reactionsNuclear reactions produces high amount of energy and many waste materials which are non degradable and will stay in the environment for the long time.
Hence, nuclear waste must be safely stored for many years.
To know more about nuclear power, visit the below link:
https://brainly.com/question/11963586
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Fiona is examining a material. She notices that the material has a dull appearance and feels very brittle.
Fiona is most likely examining a _______
(I'll give brainliest)
"Typical nonmetals have a dull, coloured or colourless appearance; are brittle when solid; are poor conductors of heat and electricity; and have acidic oxides." - Wikipedia
A community includes
A. all of the living organisms in a specific place at a specific time,
B. all plants, animals, minerals, and water in a specific place at a specific time,
C. only the plants in a specific place at a specific time.
D. only the animals in a specific place at a specific time.
Answer:
answer: A. all of the living organisms in a specific place at a specific time
Explanation:
