Answer:
The cause of periodicity in properties is the repetition of similar outer electronic configuration after certain regular intervals. For example, all the elements of group 1 i.e. alkali metals have a similar outer electronic configuration, ns1.
A gold ring is endless and has a certain diameter, it has luster, shine and other metallic properties and cash value that is not the same as raw gold.
Answer is: 8,7g.
Chemical reaction: 2Al + 6HCl → 2AlCl₃ + 3H₂.
m(Al) = 78,4g.
n(Al) = m(Al)÷M(Al) = 78,4g ÷ 27g/mol = 2,9 mol.
n - amount of substance.
from reaction: n(Al) : n(H₂) = 2 : 3.
2,9mol : n(H₂) = 2 : 3.
n(H₂) = 4,35 mol.
m(H₂) = n(H₂)·M(H₂) = 4,35mol · 2g/mol = 8,7g.
Answer:
= 200 mL
Explanation:
Using the dilution formula;
M1V1 = M2V2 ;
Where, M1 is the concentration before dilution, V2 is the volume before dilution, while M2 is the concentration after dilution and V2 is the volume after dilution.
M1 = 2.0 M
V1 = 50 mL
M2 = 0.50 M
V2 = ?
V2 = M1V1/M2
= ( 2.0 × 50 )/ 0.5
= 200 mL
Therefore, the volume after dilution will be, 200 mL
