True.
A catalyst is a substancr that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.
Answer:
The amount of molecules → 6.02×10²³
Explanation:
Avogadro Number (NA) is the amount of particles that are contained in 1 mol of anything.
It does not matter the mass of compounds, or molecules, 1 mol has 6.02×10²³ particles, the same number for every compound.
1 mol of H₂O that weighs 18 grams has 6.02×10²³ molecules
1 mol of sucrose, that weighs 342 g has 6.02×10²³ molecules
Generally, the NA is the number of atoms in 12 grams of the carbon-12 isotope.
Answer: 
Explanation:
According to ideal gas equation:

P = pressure of gas = 0.987 atm
V = Volume of gas = 12 L
n = number of moles = 0.50
R = gas constant =
T =temperature = ?


Thus the temperature of a 0.50 mol sample of a gas at 0.987 atm and a volume of 12 L is 
These could all go either way, hardness and other special properties are what I'm guessing would be the most accurate in determining the kind of material.
luster, cleavage, streak, and color can all be affected by other factors. but I guess cleavage would also be accurate. so I guess hardness special properties and cleavage would be the most reliable.
We are given the number of moles:
O = 1.36 mol
H = 4.10 mol
C = 2.05 mol
To get the empirical formula, first divide everything by
the smallest number of moles = 1.36 mol. So that:
O = 1 mol
H = 3 mol
C = 1.5 mol
Next step is to multiply everything by a number such that
all will be a whole number. In this case, multiply by 2 to get a whole number
for C, so that:
O = 2 mol
H = 6 mol
C = 3 mol
Therefore the empirical formula of the compound is:
C3H6O2