What is the percent composition (by mass) of MgBr2?
Answer:
13.2% Mg, 86.8% Br
Explanation:
Mg has a molar mass of 24.31g/mol.
Bromine has a molar mass of 79.90 g/mol.
There is one mole of Mg and two moles of Br in the compound:
79.90x2 + 24.31 = 184.11
So the total molar mass of MgBr2 is 184.11.
A percent tells us a part of a whole, so we will divide each part of the mass into the whole mass.
24.31g Mg / 184.11g MgBr2 = .132
159.8g Br / 184.11g MgBr2 = .868
Multiply these decimals by 100 to make them into a percent.
.132 x 100 = 13.2% Mg
.868 x 100 = 86.8% Br
Can you build a fire on the moon? Why or why not?
Answer:
No.
Explanation:
We can't build a fire on the moon, because moon's atmosphere lacks oxygen.
[tex] \huge \pink{answer}[/tex]
No lightning of a fire on the surface of the moon is impossible..
[tex] \huge \green {reasons - }[/tex]
surface of the moon lacks oxygen which is important for the formation of fire.Surface of the moon doesn't have wind which disables the fire to burn rapidly.Which statement is correct?
A. Physical changes produce new substances; chemical changes do not.
B. Chemical changes produce new substances; physical changes do not.
C. Both physical changes and chemical changes produce new substances.
D. Neither physical changes nor chemical changes produce new substances.
Answer:
B. Chemical changes produce new substances; physical changes do not.
Explanation:
Physical changes only alter appearances, while chemical changes are interactions that create new chemical formulas.
Oleic acid's melting point is 14°C and it's boiling point is 360°С. What phase is this substance
at room temperature 25°C?*
A. Solid
B. Liquid
C. Gas
D. Impossible to tell
is it true or false?
Answer:
The rainforest is teeming with animals and insects, so you would hear humming. Frogs and birds make some of the loudest rainforest sounds.
howler monkeys, are the loudest so i think that its false cause lost of animals are there but some can be quiet
How is a calorimeter used in this experiment different from the ones used to find the energy content of a snack
Answer:
Kindly check the explanation section.
Explanation:
PS: Note that enough information are not being provided and we do not know the experiment this question is all about. However, some information are provided below which is going to aid in solving when you get access to the main question.
The determination of the heat transferred from one substance to another is one of the important aspect in science. The method in which this heat is being measured is known as calorimetry and the instrument used in this technique is known as the calorimeter.
When the energy content of a snack is needed to be calculated, there is the need use a type of instrument known as bomb calorimeter.
Most of the calorimeters used by students are not so expensive like the used in the industries. Most of these calorimeters operates at a constant pressure while the Bomb Calorimeter operates at constant volume.
Calcium carbonate decomposes into
calcium oxide and carbon dioxide.
The mass of calcium carbonate that
decomposes is 57 g. At the end of
the experiment, the mass of the
products were only 45 g. What can
we conclude from this information?
Answer:
The mass of carbon dioxide formed is 12g.
19) Which one of the following statements describes a chemical property of hydrogen gas?
A) Hydrogen gas has a density of 0.00009 g/cm’ at STP.
B) Hydrogen gas burns in air.
C) Hydrogen gas has a boiling point of 20. K at standard pressure.
D) Hydrogen gas is colorless.
4. A girl walked for 30 minutes. She noticed that she traveled farther in the first 15 minutes of
her walk than in the second 15 minutes,
What can she conclude about her walk?
A she walked over many hills
B
her average speed was faster during the first part of her walk
C. she walked in two different directions
D. she was walking at a constant speed
You are melting a chocolate and accidentally have the stove up to high. the chocolate starts to burn on the bottom of your pot. Physical or Chemical Change?
Answer:
it is a chemical change because it can't be change back to it normal position when it gets burnt
Determine from the balanced chemical reaction if
the derived mole ratio is correct or incorrect.
2FeBr3 + 3Na2S → Fe2S3 + 6NaBr
2 moles FeBra
3 moles Na2S
Answer:
Correct
Explanation:
According to the balanced chemical reaction, 2 mol FeBr3 are consumed for every 3 mol Na2S consumed.
A balanced equation obey the law of conservation of mass. The coefficients are the numbers which are added to balance the chemical equation. Here the given mole ratio is correct.
What is a balanced equation?An equation in which the number of atoms of reactants and products on both sides of the equation are balanced is defined as the balanced chemical equation. The coefficients which are added in front of the formula of each component represents the number of the species.
A molar ratio denotes the ratio between the amounts in moles of any two compounds involved in a balanced chemical reaction. By comparing the coefficient of each component, the mole ratio can be determined.
Here for the given reaction, for every 3 moles of Na₂S consumption 2 moles of FeBr₃ is also consumed. So the molar ratio of Na₂S to FeBr₃ is 2/3. Molar ratios are used as the conversion factors between products and reactants in many chemistry problems.
To know more about mole ratio, visit;
https://brainly.com/question/29095152
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Two tons of water is pumped into a tank 15 ft. High in 5 minutes. Determine the power output of the pump. (Note: One ton is equal to 2,000 lb. And remember to convert the minutes to seconds.)
Answer:
200 lb•ft/s
Explanation:
From the question given above, the following data were obtained:
Force (F) = 2 tons
Time (t) = 5 mins
Height (h) = 15 ft
Power (P) =?
Next, we shall convert 2 tons to pound. This can be obtained as follow:
1 ton = 2000 lb
Therefore,
2 tons = 2 × 2000
2 tons = 4000 lb
Next, we shall convert 5 mins to seconds. This can be obtained as follow:
1 min = 60 s
Therefore,
5 mins = 5 × 60
5 mins = 300 s
Finally, we shall determine the power of the pump. This can be obtained as follow:
Force (F) = 4000 lb
Time (t) = 300 s
Height (h) = 15 ft
Power (P) =?
P = F × h / t
P = 4000 × 15 / 300
P = 60000 / 300
P = 200 lb•ft/s
Thus, the power of the pump is 200 lb•ft/s
Answer:
It's 200 ft-lb/sec
Explanation:
I did it before!
Determine the representative particles of
0.075 mol Ti
2.10 mol CO2
Answer:
0.o75 mol Ti = 4.5x10∧22
2.10 mol CO2 = 1.26x10∧24 molecules
hope this helped
Can someone double check my work? (Ideal Gas Law Equation)
I am solving for the amount of moles in two gases.
For one, it was 4.75mL at 0.5C (273.65K) and 1.2atm.
n=(1.2*4.75)/(0.0821/273.65)=(5.7/22.456)=0.25361653 moles
For the other gas, it was 4.6mL at 0.5C and 1.2atm.
n=(1.2*4.6)/(0.0821/273.65)=(5.52/22.456)=0.24581403 moles
Please double check these for any errors in math or whatever. Thank you.
I did not see any errors, i may be wrong but what i can see is that it is correct
Different substances have....
A.the same properties
B. different properties
C.similar properties
D.all properties
Answer:
Different properties
Explanation:
They are different.
helllllppppppp pleaseeeeeee
What is the mass in grams of 4.8 moles of Calcium Hydroxide?
Answer:
355.2 grams
Explanation:
m = M×n= (40 + 2(16+1))×4.8= 355.2 (g)
what is the pH when h+=0.045 M?
Answer:
pH≈1.35
Explanation:
-log(0.045)≈1.35
As the randomness of a system increases, the entropy of the system:
A) decreases
B) increases
C) remains the same
Answer:
it most likely increases
object with a mass of 30 kg is observed to accelerate at the rate of 4 m/s2. Calculate the force required
Colin decided to investigate soil erosion by water. He measured rates of erosion on
model hills made of soil, rock, and sand. Which of the following was the test
(independent) variable?
Answer:
i just had a test on this with 2 attempts and got it wrong on both but i do know that the answer is not...
the steepness of the models hillside
or
the rate of erosion on the hills
so the answer is either...
the amount of water sprayed on the hills
or
the type of material used to construct the model hills
but i think its the amount of water sprayed on the hills...i hope i helped a lil ;)
Explanation:
Ammonia (NH3) dissolved in water is heated in a beaker. If initially there had been 60 grams dissolved in 100 grams of water, what would happen if the temperature reached 90℃ and why? A. The solution would become supersaturated and the ammonia would all remain dissolved . B. The solution would become saturated but the amount of ammonia dissolved would remain the same . C. about 50 more grams of ammonia would be able to dissolve as the solution has become unsaturated . D. about 50 grams of ammonia would come out of solution as the temperature caused the solubility to decrease .
Answer:
C. About 50 more grams ammonia would be able to dissolve as the solution has become unsaturated
Explanation:
From the question, we have;
The mass of ammonia dissolved in water = 60 grams
The mass of the water solvent which dissolves the ammonia = 100 g
The temperature to which the ammonia water solution is raised = 90°C
Therefore, given that the solubility of a solute in a solvent increases with temperature, when the temperature is raised, we have, that the solution will more unsaturated and will be able to dissolve more ammonia, therefore, option 'C' is the most correct option that corresponds with the relationship of temperature and solubility
help please see attached file
Answer:
balanced equation of glucose
6CO2 + 6H2O----------C6H12O6 + 6O2
in the presence of sun light.
What number is pointing to the area where magma is less dense due to
heat?
Answer:
I think it's 2
Explanation:
The magma gets so hot, it floats up before cooling and sinking again
Plants and animals need to protect themselves to survive. Select the statement that best describes the adaptions of animals and plants.
Which is an example of a chemical change?
A. heating a block of ice to form liquid water
B. heating a tungsten wire until it glows brightly
C. adding sugar crystals to water to form a clear, colorless liquid
D. passing an electric current through water to form hydrogen and oxygen
Answer:
D. passing an electric current through water to form hydrogen and oxygen
Explanation:
only one that's not just a physical change.
HELP!! 30 POINTS!!!! What does the energy graph look like for this reaction??
C3H8+5O2 -> 3CO2+4H2O
I have the data, I just need to know how to make the graph, please!!
total enthalpy of reactants= -103.85
total enthalpy of products= =-2147.81
=-2043.96 kJ/mol exothermic reaction
Answer:
Bottle Nose Dolphin ummmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm
Explanation:
If you had 14.5 moles of gold, how many atoms would you expect to have?
Answer:
(14.5 mol) x (6.022 x 10^23 atoms/mol) = 8.73 × 10^24 atoms
Explanation:
pls mark brainliest
Sulfuric acid reacts with aluminum hydroxide by double replacement producing aluminum sulfate and water Write chemical reaction. If 30 g of sulfuric acid reacts with 25 g of aluminum hydroxide, identify the limiting reactant?
Answer: [tex]H_2SO_4[/tex] is the limiting reagent.
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The balanced chemical equation is:
[tex]3H_2SO_4(aq)+2Al(OH)_3(aq)\rightarrow Al_2(SO_4)_3(aq)+6H_2O(l)[/tex]
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} H_2SO_4 =\frac{30g}{98g/mol}=0.31moles[/tex]
[tex]\text{Moles of} Al(OH)_3=\frac{25g}{78g/mol}=0.32moles[/tex]
According to stoichiometry :
3 moles of [tex]H_2SO_4[/tex] require = 2 moles of [tex]Al(OH)_3[/tex]
Thus 0.31 moles of [tex]H_2SO_4[/tex] will require=[tex]\frac{2}{3}\times 0.31=0.21moles[/tex] of [tex]Al(OH)_3[/tex]
Thus [tex]H_2SO_4[/tex] is the limiting reagent as it limits the formation of product and [tex]Al(OH)_3[/tex] is the excess reagent.
if life had existed during thie won the fossils probably would not have survived because
Answer:
because life would have use fossil for their benefits.