Question 17:
False; cutting hair would change what it looks like but, braiding it keeps it the same substance it is.
Question 18 :
My best guess would either be A or D. I would lean more towards D because if there are different mixtures then it depends on what you are mixing.
Hope it helps in some way. <3
According to Kepler's second law of orbital motion, a plane's orbital speed changes , depending on how far it is from the sun. The closer a planet is to the sun, the stronger the sun's gravitational pull on it, and the faster the planet moves. The farther away from the sun, the weaker the sun's gravitational pull and the slower it moves in its orbit.
The orbit of a planet around the sun is not a perfect circle, but an ellipse - a flattened circle.
Answer: Heterogenous mixtures are the ones in which we can see the different components clearly. Air is considered to be homogenous, because we don't see the different noble gases' particles floating around. Salt water is also homogenous, because salt dissolves almost completely into water, becoming hard to see without the proper equipment salt particles in it. Steel is also homogenous, since the metals that compose it are mixed during the heating. The only heterogenous would be soil, because we can see different particles in it, with different sizes, shapes, colors, etc without having to use special equipment.
Here we apply the Clausius-Clapeyron equation:
ln(P₁/P₂) = ΔH/R x (1/T₂ - 1/T₁)
The normal vapor pressure is 4.24 kPa (P₁)
The boiling point at this pressure is 293 K (P₂)
The heat of vaporization is 39.9 kJ/mol (ΔH)
We need to find the vapor pressure (P₂) at the given temperature 355.3 K (T₂)
ln(4.24/P₂) = 39.9/0.008314 x (1/355.3 - 1/293)
P₂ = 101.2 kPa
