The correct answer is C. The weight downward and the friction moving forward creates thermal energy through kinetics and melts a tiny bit of the ice making it slick enough for the skate to slide.
Answer: 
Hz
Explanation: Recall the formula for the speed of light is
where 
is the speed of light,
is the wavelength, and 
is the frequency. Assuming this takes place in a vacuum, 
m/s. Now we can solve for frequency
(rounding to 3 sig figs)
Thus, the frequencyis Hz.
Answer:
1.3 mol H₂O
Explanation:
Let's consider the decomposition reaction of ammonium perchlorate.
NH₄ClO₄(s) → 1/2 N₂(g) + 1/2 Cl₂(g) + O₂(g) + 2 H₂O(g)
As we can see in the balanced equation, the molar ratio of ammonium perchlorate to water is 1:2. The moles of water produced by the reaction of 2.5 mol of ammonium perchlorate.
2.5 mol NH₄ClO₄ × (2 mol H₂O / 1 mol NH₄ClO₄) = 1.3 mol H₂O
P = 2.00 atm = 2026.50hPa
T = 27°C = 300K
m = 14.0g |
Mr = 28g/mol | n = m/M = 14g/28g/mol = 0,5mol
R = 83.1 [hPa*L]/[mol*K]
pV = nRT
nRT 0,5mol * 83.1[hPa*L]/[mol*K] * 300K
V = ---------- = ----------------------------------------------------------- = <u>6.15L</u>
p 2026.5hPa
Answer B.
