Lead is heavier and more resistant. Plastic foam is light and can easily be broken
Volume percent = Volume of solute
----------------------------------
Volume of the solution
2 Volume of the solute
------- = ------------------------------
100 250
Volume of the solute = 2 x 250
------------
100
= 5 mL.
Hope this helps!
Answer: D
Explanation: Convection transfers heat by movement such as air and water.
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
It is an endothermic reaction, the chemicals (probably water and ammonium nitrate) require more energy to react therefore it absorbs heat from it's surrounding to power the reaction and thus lowering the surrounding temperature. <span />