Answer:
-74.6 kj/mol
Explanation:
you can see the answer at the pic
Answer:
9x+y+8
Explanation:
We know this because you add 3x and 6x to get 9x
then we only have one y so put y by itself then subtract 15 and y which gets us 8
Answer:
78.3 × 10²³ atoms of helium are present in 52 g.
Explanation:
Given data:
Mass of He = 52 g
Number of atoms = ?
Solution:
First of all we will calculate the number of moles of He
Number of moles = mass /molar mass
Number of moles = 52 g/ 4 g/mol
Number of moles = 13 mol
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
1 mole = 6.022 × 10²³ atoms of helium
13 mol × 6.022 × 10²³ atoms of helium / 1 mole
78.3 × 10²³ atoms of helium
Answer:
8.34 moles
Explanation:
We are given 8.34 moles.
We need to find moles: 8.34
Answer:
Picking up marbles and placing them in a sack
Explanation:
The entropy of a chemical system is defined as the measure of disorder. Therefore a negative change in entropy is the movement to a more ordered state. The only option here which achieves a more ordered state, would be the first option.
Picking up marbles and placing them in a stack achieves more order, rather than the other options - that achieve more disorder.
