Answer:
True True False
Explanation:
Valves are in most veins (to prevent backflow). Also valves in the chart and an in an combustion engine.
So the first statement is True.
Valves control the flow rate and direction of fluid within a closed system. So the second statement is True.
1 Pa = 1 N/m² So since 1 Pa equals to one newton per square metre the third statement is False.
The addition of heat causes the individual particles of a solid to
Answer:
Move rapidly or move fast and farther apart. Hope this helps.
Answer: vibrate more rapidly
Explanation:
Compare and contrast the dynamics of energy transfer between the Eocene Period and the Cryogenian Period. In which period would you say that Earth's system is experiencing a net gain in energy and in which period would you say that Earth's system is experiencing a net loss in energy
Answer:
The Eocene Period is experiencing net gain in energy while Cryogenian Period is experiencing a net loss in energy.
Explanation:
In Eocene Period, the population of mammals such as horses , whales and bats etc were high due to the presence of high amount of food and good atmospheric condition such as high temperature while the population of animals were low in Cryogenian Period due to the presence of very low temperature which experiencing loss of energy. Most of area of the earth consist of icy desert.
If the mole fraction of sulfuric acid H2SO4 is 0.432 what is the percent by mass of H2SO4.
Answer:
19.47%
Explanation:
The percentage by mass of [tex]H_2SO_4[/tex] would be 19.47%.
The percentage by mass of a substance in solution is calculated as:
[tex]\frac{mass of substance}{mass of substance + water} * 100%[/tex]
Given that the mole fraction of [tex]H_2SO_4[/tex] = 0.432
The total number of mole fraction of a solution = 1
Hence, mole fraction of water = 1 - 0.432 = 0.568
Mass of water = molar mass x mole
= 98.079 x 0.432 = 42.37 g
Mass of [tex]H_2SO_4[/tex] = molar mass x mole
= 18.02 x 0.568 = 10.24 g
Hence,
%mass of [tex]H_2SO_4[/tex] = [tex]\frac{10.24}{10.24 + 42.37} * 100[/tex]
= 19.47%
0.450 moles of K2SO4 are dissolved in 195.0 mL of water. Calculate the molarity of the solution.
Answer:
2.31M
Explanation:
The following data were obtained from the question:
Mole of K2SO4 = 0.450 mole
Volume of water = 195.0 mL = 195/1000 = 0.195L
Molarity =...?
Molarity is defined as the mole of solute per unit litre of the solution. This can be expressed as:
Molarity = mole /Volume
With the above formula we can calculate the molarity of the K2SO4 solution as follow:
Molarity = mole /Volume
Molarity = 0.450/0.195
Molarity = 2.31M
Do metals or nonmetals have the greatest tendency to lose electrons and become positive ions?
Answer:
The metals have the tedency to lose electrons and become positive ions
Explanation:
In order to attain noble gases electronic configuration, metals of group I A lose one electron and II A lose 2 electrons with ionization energy.
A student observes the chemical process described by this equation:
4Al + 3O2 → 2Al2O3
How does the mass of the new substance compare to the total mass of the starting materials?
Answer:
Both are equal
Explanation:
Mass of starting material i.e Aluminium is [tex]4.480 * 10^{-23}[/tex] grams
The weight of oxygen is [tex]2.65 * 10^{-23}[/tex]
There are 4 atoms of aluminium and 3 atoms of oxygen
Thus, the total mass of starting material is
[tex]4 *[/tex] mass of one atom of aluminium [tex]+ 6 *[/tex] mass of one atom of oxygen
[tex]4 * 4.480 * 10^{-23} + 6* 2.65 * 10^{-23}[/tex]
[tex]35.1 * 10^{-23}[/tex] grams
Mass of new substance is also equal to
[tex]4 *[/tex] mass of one atom of aluminium [tex]+ 6 *[/tex] mass of one atom of oxygen
[tex]4 * 4.480 * 10^{-23} + 6* 2.65 * 10^{-23}[/tex]
[tex]35.1 * 10^{-23}[/tex] grams
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:
11. Calculate the energy required to produce 12.00 mol of CI207 on the basis of the
following balanced equation.
2012(g) + 702(g) + 130 kcal yields 201207(9)
Answer: 780 kcal are required to produce 12.00 mol of [tex]Cl_2O_7[/tex]
Explanation:
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and written along with reactants.
The balanced chemical reaction is:
[tex]2Cl_2(g)+7O_2(g)+130kcal\rightarrow 2Cl_2O_7(g)[/tex]
According to stoichiometry :
2 moles of [tex]Cl_2O_7[/tex] are produced by absorption of energy = 130 kcal
Thus 12.00 moles of [tex]Cl_2O_7[/tex] are produced by absorption of energy = [tex]\frac{130}{2}\times 12.00=780kcal[/tex]
Thus 780 kcal are required to produce 12.00 mol of [tex]Cl_2O_7[/tex]
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 .
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:
How is gold related to suns life cycle?
Answer: Gold is shiny and bright just like the sun. Gold is yellow.
Explanation:
What are all of the possible products of the electrolysis of Sodium Chloride in aqueous solution of water when the electrodes are made of copper?
A photo has been provided to show what is happening
Answer:
HDHERFEHFFFHRF
Explanation:
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
Blast furnaces extra pure iron from the Iron(IIl)oxide in iron ore in a two step sequence. In the first step, carbon and oxygen react to form carbon monoxide:
2C(s)+O2(g) arrow 2CO(g)
In the second step, iron(lll) oxide and carbon monoxide react to form Iron and carbon dioxide:
Fe203(s) + 3CO(g) arrow 2Fe(s)+ 3CO2(g)
Suppose the yield of the first step is 71.% and the yield of the second step is 72.%. Calculate the mass of oxygen required to make 7.0 kg of iron.
Be sure your answer has a unit symbol, if needed, and is rounded to 2 significant digits.
Answer:
5.9 kg
Explanation:
We must work backwards from the second step to work out the mass of oxygen.
1. Second step
Mᵣ: 55.84
Fe₂O₃ + 3CO ⟶ 2Fe + 3CO₂
m/kg: 7.0
(a) Moles of Fe
[tex]\text{Moles of FeO} = \text{7000 g Fe} \times \dfrac{\text{1 mol Fe}}{\text{55.84 g Fe}} = \text{125 mol Fe}[/tex]
(b) Moles of CO
[tex]\text{Moles of CO} = \text{125 mol Fe} \times \dfrac{\text{3 mol CO}}{\text{2 mol Fe}} = \text{188 mol CO}[/tex]
However, this is the theoretical yield.
The actual yield is 72. %.
We need more CO and Fe₂O₃ to get the theoretical yield of Fe.
(c) Percent yield
[tex]\begin{array}{rcl}\text{Percent yield} &=& \dfrac{\text{ actual yield}}{\text{ theoretical yield}} \times 100 \, \%\\\\ 72. \, \% & = & \dfrac{\text{188 mol}}{\text{actual yield}} \times 100 \,\%\\\\0.72 &= &\dfrac{\text{188 mol}}{\text{actual yield}}\\\\\text{Actual yield} & = & \dfrac{\text{188 mol}}{0.72}\\& = & \textbf{261 mol}\\\\\end{array}[/tex]
We must use 261 mol of CO to get 7.0 kg of Fe.
2. First step
Mᵣ: 32.00
2C + O₂ ⟶ 2CO
n/mol: 261
(a) Moles of O₂
[tex]\text{Moles of O}_{2} = \text{261 mol CO} \times \dfrac{\text{1 mol O}_{2}}{\text{2 mol CO}} = \text{131 mol O}_{2}[/tex]
(b) Mass of O₂
[tex]\text{Mass of O}_{2}= \text{131 mol O }_{2} \times \dfrac{\text{32.00 g O}_{2}}{\text{1 mol O}_{2}} = \text{4180 g O}_{2}[/tex]
However, this is the theoretical yield.
The actual yield is 71. %.
We need more C and O₂ to get the theoretical yield of CO.
(c) Percent yield
[tex]\begin{array}{rcl}71. \, \% & = & \dfrac{\text{188 mol}}{\text{actual yield}} \times 100 \,\%\\\\0.71 &= &\dfrac{\text{4180 g}}{\text{actual yield}}\\\\\text{Actual yield} & = & \dfrac{\text{4180 g}}{0.71}\\\\& = & \text{5900 g}\\& = & \textbf{5.9 kg}\\\end{array}[/tex]
We need 5.9 kg of O₂ to produce 7.0 kg of Fe.
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
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
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.
Which sequence represents the relationship between temperature and volume as explained by the kinetic-molecular theory?
higher temperature → more kinetic energy → more space between particles – higher volume
higher temperature → less kinetic energy → less space between particles higher volume
o higher temperature → more kinetic energy → less space between particles → lower volume
higher temperature → less kinetic energy → more space between particles lower volume
Answer:
higher temperature → less kinetic energy → less space between particles higher volume
Explanation:
How many Liters are in 17.3 moles of Iron?
Answer:
There are 0.12269 Liters of Iron
Explanation:
First, by means of the molecular weight equation, the grams of iron corresponding to 17.3 moles can be calculated:
[tex]MW=\frac{mass(grams)}{moles}[/tex]
[tex]mass=MW*moles=55.845\frac{g}{mol} *17.3mol=966.119 g[/tex]
Then using the density equation the iron milliters are calculated:
[tex]d=\frac{mass(g)}{volume(mL)}[/tex]
[tex]volume=\frac{mass}{density}=\frac{966.119g}{7.874\frac{g}{mL} } =122.69 mL[/tex]
Milliliters to liters are converted:
122.69 mL = 0.12269 L of Iron.
Answer:
[tex]V_{Fe}=0.125L[/tex]
Explanation:
Hello,
In this case, given the moles of iron, we need to use it atomic mass (55.845 g/mol) and density (7.874 g/cm³) in order to firstly convert from moles to grams and secondly from grams to cubic centimetres:
[tex]V_{Fe}=17.6molFe\times \frac{55.845gFe}{1molFe}*\frac{1cm^3}{7.874gFe}=124.8cm^3[/tex]
Finally, we obtain the volume in litres by:
[tex]V_{Fe}=124.8cm^3*\frac{1L}{1000cm^3} \\\\V_{Fe}=0.125L[/tex]
Best regards.
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!
Why were scientists surprised to find coal in the arctic?
Answer:
coal is made from compressed plant matter and how exactly did plants grow on the surface of an ocean. (as there is no land mass beneath the arctic.)
Explanation:
it would be like finding a fly in an ice cube to simplify it.
They were surprised to find coal in arctic because ordinarily coal was supposed to be found in warm or hot environments and not cold region like the arctic.
The arctic is located at the far northern part of the world which is characterized by its extreme cold weather.
A limited vegetation of plants such as grasses, mosses and lichens are found in this region irrespective of the extreme cold weather through out the year.
Coal is a type of fuel gotten from fossils and deposits of plant vegetation.
Scientist has discovered that continents do move over time through a process called continental drift. This is the reason why limited vegetaion is found in the arctic leading to the formation of coal.
Learn more here:
https://brainly.com/question/22647554
Which of these structures are found in plant cells but not animal cells?
A. Gogi apparatus
B. mitochondria
C. lysosomes
D. cell wall
Answer:
A
Explanation:
Answer:c
Explanation:
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
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
how does the Doppler effect related to the universal expanding?
An ideal gas, such as helium, is in a sealed container made of hard steel. If the container is heated, what would happen to the gas trapped inside the container?
Group of answer choices
The volume of the gas will decrease
The pressure of the gas will increase
The volume of the gas will increase
The pressure of the gas will decrease
Answer:
The correct answer is The pressure of the gas will increase
The volume of the gas will increase
Explanation:
Step 1: Data given
The gas in a container is heated, this means the temperature increases
Suppose we start with a temperature of 100 K and a pressure of 1 atm and a volume of 1L
Step 2:
V1/T1= V2/T2
⇒V1 = the initial volume = 1L
⇒T1 = the initial temperature = 100 K
⇒V2 = the new volume = TO BE DETERMINED
⇒T2 = the increased temperature = 200 K
1/100 = V2 / 200
V2 = 2 L
This means when the temperature increases, the volume will increase
P1/T1 = P2/T2
⇒P1 = the initial pressure = 1 atm
⇒T1 = the initial temperature = 100 K
⇒P2 = the new pressure = TO BE DETERMINED
⇒T2 = the increased temperature = 200 K
1/100 = P2 / 200
P2 = 2 atm
This means when the temperature increases, the pressure will increase
The correct answer is The pressure of the gas will increase
The volume of the gas will increase
A weather forecast shows 35 m/h on the weather map. Which weather component does this number represent?
A.Humidity
B. Precipitation
C.Wind direction
D.Wind speed
Answer:
D. Wind Speed
Explanation:
When the question brings up 35 m/h, the m/h stands for Miles per Hour. What option can you measure the miles per hour. Here's a hint, it applies to cars as well when cops give your parents speeding tickets. Miles per Hour = Speed. So, you are measuring the wind speed.
Why would the pressure of a sample of gas at a constant volume fall .10 atm?
Answer:
As the temperature of a sample of gas falls from 45.0ºC to 30.0ºC, its pressure falls to 300.
Explanation:
If is known how deep the water table in an area is, it is known how deep to dig to reach
Pores
The unsaturated zone
Solid rock
Groundwater
Answer:
grond water
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: