Answer:
Disposing of the discarded chemicals can be done by certain sfae methods mention as follows:
Explanation:
Most of the chemical wastes are dispose through the EHS waste program. Organic chemicals and solvents that can not be drain should be closed in a tight fitted container that has label on it as Hazardous waste, including strong acid and corrosive liquids.
Recycling of these chemicals and incineration is also use for the industrial chemical waste under professional guidance. Incineration is the process of burning chemicals in to ash through high thermal burning.
The molar mass of naphthalene is calculated as follows,
10 x (12.01 g/ mol) + 8 x (1.01 g/mol) = 128.12 g/mol
Divide the given mass by the molar mass to determine the number of moles of naphthalene present in the ball.
n = 1.52 g / 128.12 g/mol = 0.01186 mole
Multiply the number of moles to number of moles per mole.
(0.01186 mol) x (6.022 x10^23 molecules / mole) = 7.14 x 10^21 molecules
Answer: The ∆Hf is -384.7kj/mol
Explanation:
H2O +SO3-----H2SO4
-285.8 +(-98.9------- -384.7kj/mol
Answer : B) In step 2, there was a chemical change which was observed in sugar.
Explanation : In A step 2 there was a physical change that was seen. By just boiling the dissolved salt solution salt was obtained. Therefore, it is a physical change. In B step 2 there was a chemical change seen as sugar solution was thickened and turned brown. It was not obtained in its original form; there was a chemical reaction that took place during sugar evaporation. As chemical change is the one where the reaction is irreversible.
Therefore only in B step 2 there was a chemical change that was observed.
<u>Answer</u>:
mass of magnesium oxide is 4.2 grams.
<u>Explanation</u>:
Balanced equation: 2Mg + O2 → 2MgO.
Given that 2.5 g Mg reacts with 3.0 g O2
- mass = moles * Mr
- moles = mass/Mr
- Mr = mass/moles
First find the moles of Mg:
moles = mass/Mr
moles = 2.5/ 24
moles = 0.104 moles
Using molar ratio, magnesium oxide will have same moles as Mg as they both have "2" molar ratio. So moles of Mg is 0.104 moles.
mass = moles * Mr
mass = 0.104 * 40
mass - 4.1667 g
mass = 4.2 g ___________this is the mass of MgO
