For this, we first calculate molecular weight of MgSiO₃:
Atomic masses:
Mg = 24
Si = 28
O = 16
Mr = 24 + 28 + 16 x 3
Mr = 100
moles = mass / Mr
moles = 237 / 100
moles = 2.37
Answer:
3.43×10¹ mol
Explanation:
Given data:
Initial number of moles = 12.4 mol
Initial volume = 122.8 L
Final number of moles = ?
Final volume = 339.2 L
Solution:
The number of moles and volume are directly proportional to each other at same temperature and pressure.
V₁/n₁ = V₂/n₂
122.8 L/ 12.4 mol = 339.2 L / n₂
n₂ = 339.2 L× 12.4 mol / 122.8 L
n₂ = 4206.08 L.mol /122.8 L
n₂ = 34.3mol
In scientific notation:
3.43×10¹ mol
Answer:
Number of molecules = 23.9 × 10²³ molecules
Number of moles = 3.97 mol
Explanation:
Mass of HNO₃ = 250 g
Number of moles = ?
Number of molecules = ?
Solution:
Number of moles = mass / molar mass
Number of moles = 250 g/63 g/mol
Number of moles = 3.97 mol
Number of molecules:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 250 g of HNO₃:
250 g/ 63 g/mol = 3.97 mole
3.97 × 6.022 × 10²³ molecules = 23.9 × 10²³ molecules
<span>Lewis acids and bases are most closely associated with ELECTRON TRANSFER. A Lewis acid is defined as as a chemical specie that can accept an electron pair from a Lewis base to form a Lewis adduct while a Lewis base is defined as a specie which can donate an electron pair to a Lewis acid or an acceptor compound. Thus, Lewis base and acid has to do with electrons transfer.</span>
Answer:
Final T° is 45.5°C
Explanation:
Formula for calorimetry is:
Q = m . C . ΔT , where
ΔT = Final T° - Initial T°
C = Specific heat
m = mass
Let's replace with the data given
305 J = 93.4 g . 0.128 J/g°C . (Final T° - 20°C)
305 J / 93.4 g . 0.128 J/g°C = Final T° - 20°C
25.5°C = Final T° - 20°C → Final T° = 25.5°C + 20°C = 45.5°C
