Zn(s) + 2HCl(aq) = ZnCl₂(aq) + H₂(g)
zinc + hydrochloric acid = zinc chloride + hydrogen
Answer:
option C is correct = 1.14 × 10²² molecules of CO₂
Explanation:
Given data:
Number of moles of CO₂ = 0.0189 mol
Number of molecules = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
For given question:
1 mole of CO₂ = 6.022 × 10²³ molecules of CO₂
0.0189 mol of CO₂ × 6.022 × 10²³ molecules of CO₂ / 1mol
1.14 × 10²² molecules of CO₂
Thus, option C is correct.
Answer:
The final balanced equation is :
Explanation:
Balancing in acidic medium:
First we will determine the oxidation and reduction reaction from the givne reaction :
Oxidation:
Balance the charge by adding 2 electrons on product side:
....[1]
Reduction :
Balance O by adding water on required side:
Now, balance H by adding 
on the required side:
At last balance the charge by adding electrons on the side where positive charge is more:
..[2]
Adding [1] and [2]:
The final balanced equation is :
Answer is: chemical.
Making a pancake from batter is chemical change (chemical reaction), because new substances are formed, the atoms are rearranged and the reaction is followed by an energy change.
Batter is thin dough that is poured into a pan to make pancakes.
In physical change, the same substance is present before and after the psysical change, just with different form or state of matter.
