Answer:
(a) 0.2518 g; (b) 6
Explanation:
The Law of Multiple Proportions states that when two elements A and B combine to form two or more compounds, the masses of B that combine with a given mass of A are in the ratios of small whole numbers.
That is, if one compound has a ratio r₁ and the other has a ratio r₂, the ratio of the ratios r is in small whole numbers.
(a) Methane and ethane
In methane, the mass ratio of H:C is r₁ = 0.3357:1.00.
In ethane, the mass ratio of H:C is r₂
The ratio of the ratios r = ⁴/₃
r = r₁/r₂
⁴/₃ = 0.3357/r₂
(⁴/₃)r₂ = 0.3357
r₂ = 0.3357 × ¾ = 0.2518:1
Ethane contains 0.2518 g of H for every 1 g of C.
(b) Xenon fluorides
In XeF₂, the mass ratio of F:Xe is r₁ = 0.2894:1
In XeFₙ, the mass ratio of F:Xe is r₂ = 0.8682:1
r = r₂/r₁ = 0.8682/0.2894 = 3.000:1 ≈ 3:1
XeFₙ contains three times as many F atoms as XeF₂.
n = 6
We can write the balanced equation for the galvanic cell by using the oxidation and reduction half-reactions. In the anode, Ni(s) is oxidized and produces aqueous Ni2+:
Ni(s) → Ni2+
while in the cathode, Cu2+ is reduced and deposits copper:
Cu2+ → Cu(s)
We now balance the charge of each reaction by adding electrons to the side of the equation with the greater charge:
Ni(s) → Ni2+ + 2 e-
Cu2+ + 2 e- → Cu(s)
Finally, we add the half-reactions to obtain the overall balanced equation for the galvanic cell:
Cu2+(aq) + Ni(s) → Ni2+(aq) + Cu(s)
Answer:
I think its epicenter
Explanation:
The epicenter is the point on the earth's surface vertically above the hypocenter, point in the crust where a seismic rupture begins.
Answer:
Explanation:
Density is
mass / volume = d
Mass:
840g
Volume:
7 cm x 4 cm x 10 cm = 280 cm^3
840g / 280 cm^3 = 3 g/cm^3
First, we determine the number of moles of gas present using the ideal gas equation.
PV = nRT
n = PV / RT
n = (1.4 * 226.4) / (0.082 *(27 + 273.15))
n = 12.88
Next, we use the given percentages to find the moles of helium present
Moles of helium = 0.655 * 12.88
Moles of helium = 8.44
Next, we use the formula:
Mass = moles * molar mass
Mass of helium = 8.44 * 4
Mass of helium = 33.76 grams