Answer:
<h2>0.5 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula

where n is the number of moles 
N is the number of entities
L is the Avogadro's constant which is 
6.02 × 10²³ entities
From the question we have

We have the final answer as
<h3>0.5 moles</h3>
Hope this helps you
 
        
             
        
        
        
<u>Given:</u>
Initial amount of carbon, A₀ = 16 g
Decay model = 16exp(-0.000121t)
t = 90769076 years
<u>To determine:</u>
the amount of C-14 after 90769076 years
<u>Explanation:</u>
The radioactive decay model can be expressed as:
A = A₀exp(-kt)
where A = concentration of the radioactive species after time t
A₀ = initial concentration
k = decay constant
Based on the given data :
A = 16 * exp(-0.000121*90769076) = 16(0) = 0
Ans: Based on the decay model there will be no C-14 left after 90769076 years
 
        
                    
             
        
        
        
Answer:
Explanation:
What would the answer be?
 
        
             
        
        
        
Copper has 29 protons, when dealing with Cu^2+ all that means is it lost two electrons. so now the element has 29 protons and 27 electrons. Protons are positive and electrons are negative and neutrons are neutral. So say you had an element X^2- then you have gained two more electrons so the element has an overall negative charge. hope that helps
        
             
        
        
        
Molarity = mol/liter 
0.708M = 0.098mol/L
Rearrange to find L:
0.098mol/0.708M = .138L
For every liter there is 1000 mL: 
.138L • 1000mL =138mL KOH