Answer:
The first element in the periodic table is hydrogen.
Explanation:
Hydrogen has an atomic number of one, making it the first element of the periodic table. The atomic number of an element is just the number of protons in the nucleus, so hydrogen has one proton. The neutrons and electrons do not affect the atomic number. After hydrogen with one proton comes helium with two, lithium with three, beryllium with four, and so on.
Answer:
%N = 25.94%
%O = 74.06%
Explanation:
Step 1: Calculate the mass of nitrogen in 1 mole of N₂O₅
We will multiply the molar mass of N by the number of N atoms in the formula of N₂O₅.
m(N): 2 × 14.01 g = 28.02 g
Step 2: Calculate the mass of oxygen in 1 mole of N₂O₅
We will multiply the molar mass of O by the number of O atoms in the formula of N₂O₅.
m(O): 5 × 16.00 g = 80.00 g
Step 3: Calculate the mass of 1 mole of N₂O₅
We will sum the masses of N and O.
m(N₂O₅) = m(N) + m(O) = 28.02 g + 80.00 g = 108.02 g
Step 4: Calculate the percent composition of N₂O₅
We will use the following expression.
%Element = m(Element)/m(Compound) × 100%
%N = m(N)/m(N₂O₅) × 100% = 28.02 g/108.02 g × 100% = 25.94%
%O = m(O)/m(N₂O₅) × 100% = 80.00 g/108.02 g × 100% = 74.06%
Answer:
The answer is
<h2>0.89 atm </h2>
Explanation:
To convert from kPa to atm we use the conversion
101.325 kPa = 1 atm
If
101.325 kPa = 1 atm
Then
90.23 kPa will be

We have the final answer as
<h3>0.89 atm</h3>
Hope this helps you
Answer:
H. 2 blue, 3 yellow, and 12 green
Explanation:
Aluminium atoms (Al) = Blue Beads
Oxygen Atoms (O) = Green Beads
Sulfur (S) = Yellow beads
From the compound Al2(SO4)3, the number of atoms present are;
Al = 2
S = 3
O = 12
This means the model would contain;
2 Blue beads
12 Green beads
3 Yellow beads
The correct option is; H. 2 blue, 3 yellow, and 12 green