Answer:
1. 1
2. 2
3. 6
4. 8
Explanation:
Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others. Thus, this property is typically used to determine the chemical properties of elements.
1. Li is the symbol for the chemical element known as Lithium: it has 1 valence electron. The electronic configuration of lithium is 1s²2s¹
2. Mg is the symbol for the chemical element known as Magnesium: it has 2 valence electrons. The electronic configuration of magnesium is 1s²2s²2p63s²
3. O is the symbol for the chemical element known as Oxygen: it has 6 valence electrons. The electronic configuration of magnesium is 1s²2s²2p⁴.
4. Ne is the symbol for the chemical element known as Neon: it has 8 valence electrons.
On temperature 25°C (298,15K) and pressure of 1 atm each gas has same amount of substance:
n(gas) = p·V ÷ R·T = 1 atm · 20L ÷ <span>0,082 L</span>·<span>atm/K</span>·<span>mol </span>· 298,15 K
n(gas) = 0,82 mol.
1) m(He) = 0,82 mol · 4 g/mol = 3,28 g.
d(He) = 10 g + 3,28 g ÷ 20 L = 0,664 g/L.
2) m(Ne) = 0,82 mol · 20,17 g/mol = 16,53 g.
d(Ne) = 26,53 g ÷ 20 L = 1,27 g/L.
3) m(CO) = 0,82 mol ·28 g/mol = 22,96 g.
d(CO) = 32,96 g ÷ 20L = 1,648 g/L.
4) m(NO) = 0,82 mol ·30 g/mol = 24,6 g.
d(NO) = 34,6 g ÷ 20 L = 1,73 g/L.
This is the balanced eq
N2 + 3H2 -> 2NH3
first you need to find mole of N2 by using
mol = mass ÷ molar mass.
mol N2= 20g ÷ (14.01×2)g/mol
=0.7138mol
then look at the coefficient between H2 and NH3.
it is N2:NH3
1:2
0.7138:0.7138×2
0.7138:1.4276 moles
moles of NH3 = 1.4276 moles
Explanation:
The law of conservation of mass states that the total mass of the products is equal to the total of the reactants.
A chemical change occurs because of a chemical reaction.
In a chemical reaction, the reactants are the starting substances and the products is the finishing substances. The amount of each type of atoms to start with and end with are also equal.
No matter disappears after a chemical reaction.
Answer:
The amount of matter in the new substances is the same as the original.
This is known as the law of conservation of mass.
Answer:
See below.
Explanation:
pH = - log (H+)
So the pH of 1 x 10^-7 M solution is 7.
I'm sorry but I'm not sure about what the other units mean, so Im not sure of the answer to those.
If you convert the other units to the form 1 x 10^-n then the pH will be n.
