Define mass number of an atom.

Al2O3 + Fe Yields Fe3O4 + Al need before tomorrow

ella [17]

=148.413159df2ilo4sy+al2o3+al is the answer and have a nice day :)

4 0

3 years ago

Olympic cyclists fill their tires with helium to make them lighter. Assume that the volume of the tire is 860 mL , that it is fi

nata0808 [166]

Answer:

a) the mass of air = 8.24 grams

b) the mass of helium = 1.14 grams

c) the mass difference = 7.10 grams

Explanation:

Step 1: Data given

Volume of the tire = 860 mL

Total pressure = 120 psi

Temperature = 26°C

molar mass of air = 28.8 g/mol

Step 2: Convert psi to atm

(

120 psi) (1 atm / 14.7 psi) = 8.163

Step 4: Calculate moles

PV = nRT

⇒ with P = the pressure = 8.163 atm

⇒ with V = the volume = 860 mL = 0.860 L

⇒ with n = the number of moles = TO BE DETERMINED

⇒ with R = the universal gas constant = 0.08206 L*atm/K*mol

⇒ with T = the temperature = 26 °C = 299 Kelvin

n = (8163*0.860)/(0.08206*299)

n = 0.2861 moles of gas

Step 5: Calculate the mass of air in an air-filled tire.

Mass = moles * molar mass

Mass = (0.2861 moles of gas) (28.8 g/mol)

Mass = 8.24 grams

Step 6: Calculate the mass of helium in a helium- filled tire.

mass of helium = 0.2861 moles of gas * 4 g/mol)

mass of helium = 1.14 grams

Step 7: What is the mass difference between the two?

Δmass= 8.24 grams - 1.14 grams

Δmass= 7.10 grams

8 0

4 years ago

20 points - Chemistry - plzzz help

Angelina_Jolie [31]

Answer:

1. Inversely proportional

2. Option C. Boyle's Law

3. Directly proportional

4. Option C. Gay-Lussac's Law

5. Directly proportional

6. Option C. Charles' Law

Explanation

Boyle's law states that the volume of a fixed mass of gas is inversely proportional to the pressure provided temperature remains constant. Mathematically,

V & 1/P

V = K/P

PV = K(constant)

Charles' law states that the volume of a fixed mass of gas is directly proportional to it's absolute temperature, provided pressure remains constant. Mathematically,

V & T

V = KT

V / T = K(constant)

Gay-Lussac's Law states that the pressure of a fixed mass of gas is directly proportional to it's absolute temperature, provided the volume remains constant. Mathematically

P & T

P = KT

P/ T = K (constant)

7 0

3 years ago

Which of the two forces is greater the force on the firefly or the force on the bus explain your answer please I really need hel

maksim [4K]

Answer: The force on the firefly

The unfortunate firefly hitting the bus does not change the velocity of the bus very much. Technically there is a change, but it's so very small and miniscule that it barely registers. To any casual observer not paying very close attention, they don't notice anything at all. So effectively the force on the firefly is a lot greater since the firefly got the worst end of the deal.

So in short, we look at the velocity of each object and see which velocity changed the most. In this case, the firefly's velocity changed from whatever speed it was flying to 0 when it stops flying all together. That's why the force is greater on the bug.

8 0

3 years ago

Two different bromide solutions are mixed with each other: Solution 1 is an aqueous solution of 4.85 g aluminum bromidein 150. m

erma4kov [3.2K]

Answer:

M=0.380 M.

Explanation:

Hello there!

In this case, given those two solutions of aluminum bromide and zinc bromide, it is firstly necessary to compute the moles of bromide ions in each solution as shown below:

$n_{Br^-}^{in\ AlBr_3}=4.85 gAlBr_3*\frac{1molAlBr_3}{266.69gAlBr_3}*\frac{3molBr^-}{1molAlBr_3} =0.05456molBr^-\\\\n_{Br^-}^{in\ ZnBr_2}=7.75gZnBr_2*\frac{1molZnBr_2}{225.22gZnBr_2}*\frac{2molBr^-}{1molZnBr_2} =0.06882molBr^-$