Answer:
2.89× 10²³ atom
Explanation:
Given data:
Number of atoms of Zn = ?
Number of moles of Zn = 0.48 mol
Solution:
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.
1 mole = 6.022 × 10²³ atom
0.48 mol × 6.022 × 10²³ atom / 1mol
2.89× 10²³ atom
Chemical reaction: Sr(OH)₂ + 2HNO₃ → Sr(NO₃)₂ + 2H₂O.
part A) m(Sr(OH)₂) = 21,78 g.
n(Sr(OH)₂) = m(Sr(OH)₂) ÷ M(Sr(OH)₂).
n(Sr(OH)₂) = 21,78 g ÷ 87,62 g/mol.
n(Sr(OH)₂) = 0,248 mol.
c(Sr(OH)₂) = n(Sr(OH)₂) ÷ V(Sr(OH)₂).
c(Sr(OH)₂) = 0,248 mol ÷ 0,075 L.
c(Sr(OH)₂) = 3,3 mol/L.
part B) V(Sr(OH)₂) = 34,21 mL = 0,03421 L.
n(Sr(OH)₂) = 0,03421 L · 3,3 mol/L = 0,112 mol.
From chemical reaction: n(Sr(OH)₂) : n(HNO₃) = 1 : 2.
n(HNO₃) = 0,225 mol.
V(HNO₃) = 0,225 mol ÷ 0,25 mol/L.
V(HNO₃) = 0,9 L = 900 ml.
Answer:
Correct answers: 2 and 3
Explanation:
1- correct would be: Isolation of ibuprofen is not dangerous, but it is necessary because only one enantiomer has effect on interaction with biologic <em>diana</em>
<em>2: Correct! This property of diastereomeric salts (differing solubilities) is really useful for the isolation of the original enantiomers</em>
<em>3: Correct! we can only observe their properties, like polirized light rotation or separation in an assimetric column for chromatography.</em>
4: correct would be: diastereomeric salts do not rotate light, they have lost the property of anantiomers that originated them
Answer:
The more acidic the solution the faster it rusts. More Na = more rust
Explanation:
