Answer: 600 kJ
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Explanation:
C₃H₈ (g) + 5 O₂ (g) =============== 3 CO₂ (g) + 4 H₂O (l)
Δ⁰Hf kJ/mol -104 0 -393.5 -285.8
Δ⁰Hcomb C₃H₈ = 3(-393.5) + 4 (-285.80) - (-104) kJ/mol
Δ⁰Hcomb = 2219.70 kJ/mol
n= m /MW MW c₃H₈ = 44.1 g/mol
n= 12 g/44.1 g/mol = 0.27 mol
then for 12 g the heat released will be
0.27 mol x 2219.70 kJ/mol = 600 KJ
The naturally acidic rainwater will erode the limestone mountin over time
<span>B. Hydrogen is electrically neutralized in the solution. Hydrogen is a chemical element with symbol H and atomic number 1. With a standard atomic weight of circa 1.008, hydrogen is the lightest element on the periodic table.</span>
Answer:
Explanation:40 mph = 64.3738 kph
kph/3.6 = m/s
64.3738/3.6 = 17.8816 m/s
30 mins in seconds = 30 x 60 = 1800 s
1800 s x 17.8816 m/s = 32186.88 m or 32.18688 km or 20 miles
There are several things that can help scientists evaluate which category something belongs to. The similarity in features is one of them. If two skulls looked alike, they were probably species of the same evolutionary category. For example say humans and monkeys rather than humans and dogs.
Similarly fossils have helped scientists categorise species. Study of the chromosomes (in cases with available chromosomes) can help scientists figure out a lot about the subjects and categorise them.
