<h2>Answer </h2>
Option C - 320J
<u>Explanation </u>
Since ethanol solid at −120 °C and is only cooling down (it won’t change states)
. The amount of Thermodynamic properties values c is given in form of solid, liquid and gas. Amount of energy released is calculated below.
Formula,
= change in temperature x specific heat capacity for solid ethanol x 40
=> 0.5 x 16x 40 = 320J
Therefore, the 320J of heat is released when 40.0g of ethanol cools.
Because you are never 100% precise during the work, so it's best and most accurate answer is always the average of more trials. basically the more you do, the more accurate the answer shall be
Answer:
the oxidation number of those elements is 2 because some of them are molecules
1. Gypsum has the formula as CaSO₄.2H₂O<span>. Hence, CaSO₄ is bound with two H₂O. CaSO₄ has 1 Ca atom, 1 S atom and 4 O atoms. 2H₂O have 4 H atoms and 2 O atoms.
Hence,
total Ca atoms = 1
total S atoms = 1
total O atoms = 4 + 2 = 6
total H atoms = 4
total number of atoms = 1 + 1 + 6 + 4 = 12
</span>2. Cellulose has the formula as C₆H₇O₂(OH)₃. But there are 2 molecules.<span> Hence, to find total atoms in each element, number of atoms should be multiplied by 2 .The elements of the cellulose are C, H, and O.
Hence,
total C atoms = 6 x 2 = 12
total O atoms = (2 + 3) x 2 = 10
total H atoms = (7 + 3) x 2 = 20
total number of atoms = 12 + 10 + 20 = 42
</span>
3. The formula of the antiperspirant is Al₂Cl(OH)₅<span>. It has Al, Cl, O and H as the elements. Hence, the number of atoms in each element can be found as follows;
total Al atoms = 2
total Cl atoms = 1
total H atoms = 1 x 5 = 5
total O atoms = 1 x 5 = 5
total number of atoms = 2 + 1 + 5 + 5 = 13</span>
