Answer:
The correct answer is 0.300 * 10^23 ions.
Explanation:
Based on the given question, there is a need to find the number of chloride ions in the mentioned 6.8 grams of zinc chloride compound.
The moles of zinc chloride (ZnCl2) is,
= mass of zinc + 2 mass of chlorine
= 65.38 + 2 (35.45)
=65.38 + 70.90
= 136.28 grams (The molecular mass of zinc is 65.38 and the molecular mass of chlorine is 35.45)
Thus, 136.28 g of ZnCl2 contains 70.90 grams of chlorine
Therefore, 6.8 grams of ZnCl2 will comprise = (70.90/136.28) * 6.8
= 3.537 g of chlorine
70.90 g of Cl comprise 6.022*10^23 chlorine, thus, 3.537 g of Cl will comprise (6.022*10^23/70.90) * 3.537
= 0.300 * 10^23 ions of chlorine.
Here we have to get the moles of hydrogen (H₂) consumed to form water (H₂O) from 1.57 moles of oxygen (O₂)
In this process 3.14 moles of H₂ will be consumed.
The balanced reaction between oxygen (O₂) and hydrogen (H₂); both of which are in gaseous state to form water, which is liquid in nature can be written as-
2H₂ (g) + O₂ (g) = 2H₂O (l).
Thus form the equation we can see that 1 mole of oxygen reacts with 2 moles of hydrogen to form 2 moles of water.
So, 1.57 moles of oxygen will consume (1.57×2) = 3.14 moles of hydrogen to form water.
Answer:
36
Explanation:
Since the sample was undiluted the number of colonies is the number that grew on the nutrient agar which is 36 colonies. If it was diluted for example let say 0.1 ml from a dilution in which 1 ml of the sample was added to 9 ml of water, and it grew colonies then 0.1 ml yielded 6 colonies, 1 ml of the diluted sample will yield 60 colonies and 10 ml will have 600 colonies and therefore the 1 ml undiluted sample will have 600 colonies.
There is this thing called isotopes
it means that atoms of the same element can have a different number of neutrons.
if there is a change in the no. of neutrons, there will definitely be a change in the mass number.
so the answer is A) mass number
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.
