That means that one (s) type orbital and three (p) type orbitals (all of the p orbitals in the valence set) have been mixed together to form four NEW atomic orbitals, all of equal energy, that point in specific directions (to the four vertices of a tetrahedron) the directions that the orbitals point is THE point of doing this because that enables you to explain why certain compounds like CH4 have a tetrahedral structure. It's kind of circular logic that you have to basically accept, but it makes sense if you delve deeper into the theory
Chemical reactions release or absorb heat or other energy or may produce a gas, odor, color change, or sound. If you don’t see any of these indications, a physical change likely occurred. Be aware a physical change may produce a dramatic change in the appearance of a substance. This doesn’t mean a chemical change occurred. Examples of a chemical change would be rusting iron, or burning wood, or even cooking. Examples of physical changes would be tearing paper, boiling water, or freezing popsicles.
It is an ideal gas therefore we can use the ideal gas equation to solve the problem. The ideal gas equation is expressed as PV = nRT. First, we solve the amount of the gas in moles using the said equation and the first conditions.
(2.0 atm) (5.0 x 10^3 cm^3) = n (82.0575 atm.cm^3/mol.K)(215 K)
n=0.5668 mol
Using the second conditions given, we obtain the new pressure.
P (4.0 x 10^3) = 0.5668 x <span>82.0575 x 265
P= 3.08 atm</span>
Complete question:
A spirit burner used 1.00 g methanol to raise the temperature of 100.0 g water in a metal can from 28.00C to 58.0C. Calculate the heat of combustion of methanol in kJ/mol.
Answer:
the heat of combustion of the methanol is 402.31 kJ/mol
Explanation:
Given;
mass of water, 
= 100 g
initial temperature of water, t₁ = 28 ⁰C
final temperature of water, t₂ = 58 ⁰C
specific heat capacity of water = 4.184 J/g⁰C
reacting mass of the methanol, m = 1.00 g
molecular mass of methanol = 32.04 g/mol
number of moles = 1 / 32.04
= 0.0312 mol
Apply the principle of conservation of energy;
Therefore, the heat of combustion of the methanol is 402.31 kJ/mol
