Answer:
In the calorimeter, water is the <u>exothermic</u>. The salt LiCI, which will dissolve, is the <u>endothermic</u>. The final temperature of the water after the dissolution of LiCI was <u>lower</u> than the initial temperature, meaning the process is <u>exothermic</u>. In the microscopic view of the disspolution of LiCI, water molecules were seen to move <u>slowly</u> as they <u>gained </u>energy.
Explanation:
Exothermic is a process in which heat is released during the process. Endothermic reactions absorbs heat from surrounding during a chemical process. The dissolution of salt into water is an exothermic reaction. During this process heat is release and water molecules are broken down which are surrounded by salt ions.
Answer:
Heat lost to the surroundings
Heat lost to the thermometer
Explanation:
All changes in heat, or energy, can be explained. Many of the reactions or changes we see in the world involve the conversion of energy. For example as we heat up a substance (eg. water), the amount of energy we put in should give us an exact temperature. However, this is a "perfect world" scenario, and does not occur in real life. Whenever heat is added to a substance like water, we always need to account for the energy that is going to be lost. For example, heat lost to evaporation or even the effect of measuring the temperature with a thermometer (the introduction of anything including a thermometer will affect the temperature).
The Molecule of Sodium Formate along with Formal Charges (in blue) and lone pair electrons (in red) is attached below.
Sodium Formate is an ionic compound made up of a positive part (Sodium Ion) and a polyatomic anion (Formate).
Nomenclature:
In ionic compounds the positive part is named first. As sodium ion is the positive part hence, it is named first followed by the negative part i.e. formate.
Name of Formate:
Formate ion has been derived from formic acid ( the simplest carboxylic acid). When carboxylic acids looses the acidic proton of -COOH, they are converted into Carboxylate ions.
E.g.
HCOOH (formic acid) → HCOO⁻ (formate) + H⁺
H₃CCOOH (acetic acid) → H₃CCOO⁻ (acetate) + H⁺
Formal Charges:
Formal charges are calculated using following formula,
F.C = [# of Valence e⁻] - [e⁻ in lone pairs + 1/2 # of bonding electrons]
For Oxygen:
F.C = [6] - [6 + 2/2]
F.C = [6] - [6 + 1]
F.C = 6 - 7
F.C = -1
For Sodium:
F.C = [1] - [0 + 0/2]
F.C = [1] - [0]
F.C = 1 - 0
F.C = +1
The total number of digits that are counted while performing a measurement, are called significant figures or significant numbers. In a measured number, all the digits are certain except the last digit. The last digit which is uncertain in a measured number is called estimated digit. In the measurement 543.1267 inches, the last digit 7 is estimated digit. While taking into account the total number of significant figures, we count all the certain digits plus the estimated digit. Therefore, the number 543.1267 has 7 significant figures.
Answer:
205.3 mL of ethyl alcohol
Explanation:
<em>The resulting container and liquid mixture has a mass of 512 g</em>
Mass of container + Mass of water + Mass of ethyl alcohol
150 g + 200 g + Mass of ethyl alcohol = 512 g
We know that water has a mass of 200g, cause the density, which values 1 g/mL.
200 mL are contained in 200 g of water.
Mass of ethyl alcohol = 512 g - 200 g - 150 g ⇒ 162 g
Density of ethyl alcohol = ethyl alcohol mass / ethyl alcohol volume
0.789 g/mL = 162g / ethyl alcohol volume
162 g / 0.789 g/mL = 205.3 mL
