Answer: “We live on a hunk of rock and metal that circles a humdrum star that is one of 400 billion other stars that make up the Milky Way Galaxy which is one of billions of other galaxies which make up a universe which may be one of a very large number, perhaps an infinite number, of other universes. That is a perspective on human life and our culture that is well worth pondering.”
― Carl Saga
Is this it mate?
The heat released by the substance in the calorimeter is equal to the heat absorbed by water which results to the decrease and increase in temperature, respectively.
We use m Cp ΔT to balance the heat involved
(m Cp ΔT) subs in calorimeter = <span>(m Cp ΔT) water
</span>125 g * Cp * (97.0-23.5 ) C = 250 g *(4.18 J/C g)* (23.5-20)
Cp = 0.398 J/Cg
Answer is B
The correct answer is A, B and C
Explanation:
a. Magnesium oxide is used mainly in soil treatment and groundwater remediation, wastewater treatment, etc. it is used for it's acid buffering capacity and effectiveness in dissolving heavy metals.
b. MgO is the chemical equation for the reaction.
c. multiply the given mass of O2 by the inverse of it's molar mass. multiply the molar ratio (from the balanced equation) between O2 and MgO. Multiply by the molar mass of MgO. 32g O2 x 1 mol O2 ... 32g O2 x 2mol MgO 1mol O2 x 40g MgO. .... 1mol MgO = 80 g.
d. Mg (s) + 2 HCl (aq) produces MgCl 2(aq) + H 2 (g). Where the letter "s" stands for solids, and "g" is for gas and "aq" represents aqueous solution.
The balanced equation for the combustion of octane is as follows
2C₈H₁₈ + 25O₂ ---> 16CO₂ + 18H₂O
stoichiometry of C₈H₁₈ to O₂ is 2:25
number of octane moles reacted - 17.0 g / 114.2 g/mol = 0.149 mol
according to molar ratio
if 2 mol of octane reacts with 25 mol of O₂
then 0.149 mol of octane reacts with - 25 /2 x 0.149 mol = 1.86 mol of O₂
mass of O₂ - 1.86 mol x 32 g/mol = 59.5 g
59.5 g of O₂ is required to react with
