KOH + HBr ---> KBr + H2O
0,3 moles of HBr ---in-------1000ml
x moles of HBr-------in------75ml
x = 0,0225 moles of HBr
according to the reaction: 1 mole of KOH = 1 mole of HBr
so
0,0225 moles of HBr = 0,0225 moles of KOH
0,0225 mole of KOH------in-----45ml
x moles of KOH -----------in------1000ml
x = 0,5 moles of KOH
answer: 0,5 mol/dm³ KOH (molarity)
Volume = nRT/P
n = number of particles (moles)
R = universal gas constant (0.0821)
T = temperature (Kelvin)
P = pressure (atm)
(Assuming you have 1 mole of Helium in a chemical reaction) We would need to convert grams to moles: 12.0g He x 1 mol He/4 molar mass of He = 3 mol He
Convert Celsius to Kelvin: 100*C + 273.15 = 373.15 K
Now we can set up the equation for volume: (3mol)(0.0821)(373.15)/1.2atm = 76.6 L of Helium gas
Answer:
The correct option is: stable environment
Explanation:
According to the Darwin's theory, natural selection is the concept by which all the small useful variations of traits are preserved.
According to Darwin, there are three <u>necessary and sufficient conditions</u> for the occurrence of natural selection:
1. struggle for existence
2. variation
3. inheritance
These conditions are said to be necessary because if these conditions are not satisfied then natural selection does not occur.
These conditions are said to be sufficient because if these conditions are satisfied, then natural selection will most definitely occur.
The term Rutherford gave to the positively charged particles in the nucleus of an atom was/is Proton.
Hope this helps!
Answer:
179.87 g/mol
Explanation:
First you need to determine the number of each elements in the molecule. This information comes from the molecular formula.
Ze(NO3)2 tells us that there is 1 Ze atom and 2 NO3 anions per molecule. each NO3 anion will have 1 nitrogen and 3 oxygens. Due to that, one molecule of Ze(NO3)2 will have 1 atom of Ze, 2 atoms of nitrogen (N), and 6 atoms of oxygen (O).
Next you need to add all of the individual atom's molar masses to get the over all molar masses. The molar masses of each element is in the question but it can also be found on the periodic table.
molar mass of Ze(NO3)2 = 55.85g/mol + (14.01g/mol*2) + (16.00g/mol*6)
molar mass of Ze(NO3)2 = 179.87 g/mol
I hope this helps.
