Answer:
option C is correct (250 g)
Explanation:
Given data:
Half life of carbon-14 = 5700 years
Total amount of sample = 1000 g
Sample left after 11,400 years = ?
Solution:
First of all we will calculate the number of half lives passes during 11,400 years.
Number of half lives = time elapsed/ half life
Number of half lives = 11,400 years/5700 years
Number of half lives = 2
Now we will calculate the amount left.
At time zero = 1000 g
At first half life = 1000 g/2 = 500 g
At second half life = 500 g/2 = 250 g
Thus, option C is correct.
step one
calculate the % of oxygen
from avogadro constant
1moles = 6.02 x 10 ^23 atoms
what about 4.33 x10^22 atoms
= ( 4.33 x 10^ 22 x 1 mole ) / 6.02 10^23= 0.0719 moles
mass= 0.0719 x16= 1.1504 g
% composition is therefore= ( 1.1504/3.25) x100 = 35.40%
step two
calculate the % composition of chrorine
100- (25.42 + 35.40)=39.18%
step 3
calculate the moles of each element
that is
Na = 25.42 /23=1.1052 moles
Cl= 39.18 /35.5=1.1037moles
O= 35.40/16= 2.2125 moles
step 4
find the mole ratio by dividing each mole by 1.1037 moles
that is
Na = 1.1052/1.1037=1.001
Cl= 1.1037/1.1037= 1
0=2.2125 = 2
therefore the empirical formula= NaClO2
Answer:
It would be known as a chemical reaction or a chemical compound.
<h3>
Answer:</h3>
B) 4H₂(g) + O₂(g) ⟶ 2H₂O(l)
<h3>
Explanation:</h3>
- Chemical reactions occur when compounds or elements combine to form new compounds or other elements.
- Chemical reactions may be classified into various types which include synthesis reactions, replacement reaction, decomposition reactions, and precipitation reactions among others.
- In our case, we were supposed to identify a synthesis reaction.
- Thus, we need to know what is a synthesis reaction.
- A synthesis reaction is a reaction that occurs when two elements or small compounds combine to generate a large compound.
- In this case, B is the choice that shows a synthesis reaction where hydrogen gas combines with oxygen gas to yield water.
Force is a strength or energy as an attribute or physical action or movement, motion is the action or process of moving or being moved
