Answer:
The symbol of each element is, Ne, Na, Mg, and Al.
Explanation:
Below is the list of elements that has an atomic mass of less than 19.3 u.
The atomic mass of Neon is 20.1797 u and the atomic number is 10.
The atomic mass of Sodium is 22.989769 u and the atomic number is 11.
The atomic mass of Magnesium is 24.305 u and the atomic number is 12.
The atomic mass of Aluminium is 26.981539 u and the atomic number is 13.
Here, the symbol of each element is, Ne, Na, Mg, and Al.
Three classes: 28×3=84 students
8 test tubes per student: 84× 8= 672
hope this helps!
Answer:
2H₂O₂ → 2H₂O + O₂
24.7 L are the liters of formed oxygen.
Explanation:
We state the reaction:
2H₂O₂ → 2H₂O + O₂
2 moles of peroxide decompose to 2 moles of water and 1 mol of oxygen gas.
We convert the mass to moles: 75 g . 1 mol / 34 g = 2.20 moles
As ratio is 2:1, per 2.20 moles of peroxide I would produce the half of moles, of O₂ → 2.20 /2 = 1.10 moles
We convert the moles to mass → 1.10 mol . 32 g / 1 mol = 35.3 g
Let's use oxygen's density to find out the volume
δ O₂ = 1.429 g/L (mass/volume)
35.3 g . 1L / 1.429g = 24.7 L
Answer:
3.82 × 10 ^-23 g
Explanation:
6.02 x 10^23atoms = 1 mole of sodium
1 atom = 1/(6.02 x 10^23) mole
mass = mole × molar mass
= 1/(6.02 x 10^23) × 23
= 3.82 × 10 ^-23 g
Answer:
D. The rock cycle is a series of processes in which one kind of rock is transformed into other kinds.
Explanation:
