Answer:
light is the result of electrons moving between defined energy levels in an atom called shells.
Explanation:
when something exited an atom like collision with another atom or a chemical reaction, an electron may absorb energy boosting it to a higher level shell.
Answer:
Mass = 88.12 g
Explanation:
Given data:
Mass of iron oxide = 126 g
Mass of iron formed = ?
Solution:
Chemical equation:
Fe₂O₃ + 3CO → 2Fe + 3CO₂
Number of moles of iron oxide:
Number of moles = mass/molar mass
Number of moles = 126 g/ 159.69 g/mol
Number of moles = 0.789 mol
Now we will compare the moles of iron with iron oxide.
Fe₂O₃ : Fe
1 : 2
0.789 : 2/1×0.789 = 1.578 mol
Mass of iron:
Mass = number of moles ×molar mass
Mass = 1.578 mol × 55.84 g/mol
Mass = 88.12 g
Answer:
0.96g of sodium hydride
Explanation:
Equation of reaction:
NaH + H20 = NaOH + H2
Mass of hydrogen gas produced (m) = PVM/RT
P = 765torr - 28torr = 737torr = 737/760 = 0.97atm, V = 982mL = 982cm^3, M = 2g/mol, R = 82.057cm^3.atm/gmol.K, T = 28°C = 28 + 273K = 301K
m = (0.97×982×2)/(82.057×301) = 0.08g of hydrogen gas
From the equation of reaction
1 mole (24g) of sodium hydride produced 1 mole (2g) of hydrogen gas
0.08g of hydrogen gas would be produced by (24×0.08)/2 = 0.96g of sodium hydride
Answer:
42.9%
Explanation:
the total number of coins is 15+14+6 = 35
so to find the % of pennies, divide the number of pennies by the total number of coins and times it all by 100
15/35 x 100 = 42.9%