a tick attaches itself to the skin of a dog
Answer:
MOLARITY= 0.3092mol/l
ABSOLUTE UNCERTAINTY= 0.000873
Explanation:
The equation of reaction is
2HNO3 + Na2CO3 ⟶ 2NaNO3 + H2O + CO2.
QUESTION1: CALCULATION FOR MOLARITY;
Molarity= gram mole of solute ÷ liters of solution
Where;
Mole of solute= mass ÷ molar mass
Therefore;
Mole of solute= 0.8311g ÷ 105.988g/mol= 0.0078515mol
MOLARITY= 0.0078415mol ÷ 25.36ml = 0.0003092mol/ml = 0.3092mol/l
This is the Molarity of the solution
QUESTION2: CALCULATION FOR ABSOLUTE UNCERTAINTY;
Uncertainty (u) =√([0.05 ÷ 25.36]^2 + [0.001 ÷ 105.988]^2 + [0.0007 ÷ 0.8311]^2) × Molarity
Solving brackets gives
(0.00197161+0.00000943503+0.00084226) ×Molarity
Adding up gives
0.002823×Molarity
Therefore;
ABSOLUTE UNCERTAINTY= 0.002823×0.3092= 0.000873
Answer :
Option D) 2.50 X 
Mol/(L s)
Explanation: While calculating the average reaction rate for the given reaction in terms of Cl;
.
using the rate equation which is;
![\frac{delta [Cl]}{delta t}](https://tex.z-dn.net/?f=%20%5Cfrac%7Bdelta%20%5BCl%5D%7D%7Bdelta%20t%7D%20)
=
=
2.50 X Mol/(L s)
Answer:
Mass = 65.4 g
Explanation:
Given data:
Mass of Al₂O₃ = 25 g
Mass of AlCl₃ = ?
Solution:
Chemical equation:
Al₂O₃ + 6HCl → 2AlCl₃ + 3H₂O
Number of moles of Al₂O₃:
Number of moles = mass/ molar mass
Number of moles = 25 g/ 101.96 g/mol
Number of moles = 0.2452 mol
Now we will compare the moles of Al₂O₃ and AlCl₃.
Al₂O₃ : AlCl₃
1 : 2
0.2452 : 2×0.2452 = 0.4904 mol
Mass of AlCl₃:
Mass = number of moles × molar mass
Mass = 0.4904 mol × 133.34 g/mol
Mass = 65.4 g
B) IV, because all the others are physical changes and cannot be reversed.
