Answer: C2H4 + 3O2 → 2CO2 + 2H2O
Explanation:
2Al + 2O2 → 2AlO + O2 Not Balanced Properly: 2Al + O2 = 2AlO
C2H4 + 3O2 → 2CO2 + 2H2O Looks Good
2CH4 + O2 → 2CO + 4H2 Not Correct: CO should be CO2
Ca + O2 → CaOH Not Balanced and No source for the H
Your Question: {How many objects are in a mole?}
Helpful Knowledge: (We Know the amount in an object: 12g or C^12)
{A number of objects that are in a mole of objects?}
Well for the question it is pretty easy to answer because a number of objects in One mole would equal 6.02 × 10²³
Which 6.02 × 10²³ is an Avogadro's Number.
So it depends on how many objects you have.
So for every object you have, One mole would equal 6.02 × 10²³. Or 62,000,000,000,000,0000,000,000. Big Number am I right. So that's why we just use 6.02 × 10²³.
Anywho, your answer would be 6.02 x 10²³ x n.
N would equal the number of objects you're calculating.
Final Answer: 6.02 x 10²³ x (n) = (Your Answer)
Hope this helps! Have a great day. If you need anything else, feel free to hope right in my inbox. Or comment below. ↓
Answer:
Mass = 135.66 ×10⁻²¹ g
Explanation:
Given data:
Number of molecules of CuSO₄= 5.119×10²
Mass of CuSO₄= ?
Solution:
The given problem will solve by using Avogadro number.
1 mole contain 6.022×10²³ molecules
5.119×10² molecules ×1 mol / 6.022×10²³ molecules
0.85×10⁻²¹ mol
Mass in grams:
Mass = number of moles × molar mass
Mass = 0.85×10⁻²¹ mol × 159.6 g/mol
Mass = 135.66 ×10⁻²¹ g
This question is testing to see how well you understand the "half-life" of radioactive elements, and how well you can manipulate and dance around them. This is not an easy question.
The idea is that the "half-life" is a certain amount of time. It's the time it takes for 'half' of the atoms in any sample of that particular unstable element to 'decay' ... their nuclei die, fall apart, and turn into nuclei of other elements.
Look over the table. There are 4,500 atoms of this radioactive substance when the time is 12,000 seconds, and there are 2,250 atoms of it left when the time is ' y ' seconds. Gosh ... 2,250 is exactly half of 4,500 ! So the length of time from 12,000 seconds until ' y ' is the half life of this substance ! But how can we find the length of the half-life ? ? ?
Maybe we can figure it out from other information in the table !
Here's what I found:
Do you see the time when there were 3,600 atoms of it ?
That's 20,000 seconds.
... After one half-life, there were 1,800 atoms left.
... After another half-life, there were 900 atoms left.
... After another half-life, there were 450 atoms left.
==> 450 is in the table ! That's at 95,000 seconds.
So the length of time from 20,000 seconds until 95,000 seconds
is three half-lifes.
The length of time is (95,000 - 20,000) = 75,000 sec
3 half lifes = 75,000 sec
Divide each side by 3 : 1 half life = 25,000 seconds
There it is ! THAT's the number we need. We can answer the question now.
==> 2,250 atoms is half of 4,500 atoms.
==> ' y ' is one half-life later than 12,000 seconds
==> ' y ' = 12,000 + 25,000
y = 37,000 seconds .
Check:
Look how nicely 37,000sec fits in between 20,000 and 60,000 in the table.
As I said earlier, this is not the simplest half-life problem I've seen.
You really have to know what you're doing on this one. You can't
bluff through it.
The answer is A! Hoped it’s sure!
Explanation: A chemical reaction involves breaking bonds in the reactants, rearranging the atoms into new groupings (the products), and forming new bonds in the products.
Hope I was able to help! Mark me brainly it would help a lot!
