Equation for Half life :
A = a(0.5)^(t/h)
A is current amount, "a" is initial amount, h is halflife, t is time
5 = 40(0.5)^(t/1.3x10^9)
5/40 = (0.5)^(t/1.3x10^9)
take the log of both sides , power rule
Log(5/40) = (t/1.3x10^9) * Log(0.5)
(1.3x10^9) * Log(5/40) / Log(0.5) = t
3.9x10^9 years = t
And if you think about what a half life is, the time it take for the amount to reduce to half.
40/2 = 20
20/2 = 10
10/2 = 5
It went through 3 half-lifes
3 * 1.3x10^9 = 3.9x10^9 years
<em>Maybe</em>
<em>Mg+</em><em>Fe2O3</em><em>→</em><em>F</em><em>e</em><em>+</em><em>MgO</em>
<em>hope</em><em> it</em><em> helps</em>
Answer:
A. Ba(NO₃)₂(aq) + Na₂CO₃(aq)
Explanation:
- The reaction between aqueous Ba(NO₃)₂ and Na₂CO₃ is a precipitation reaction.
- The complete equation for the reaction is;
Ba(NO₃)₂(aq) + Na₂CO₃(aq) → BaCO₃(s) + NaNO₃(aq)
- Barium carbonate is the precipitate formed during the reaction.
- All nitrates are soluble in water and all salts of sodium are soluble in water, therefore, Ba(NO₃)₂, Na₂CO3, and NaNO₃ are soluble in water.
- Precipitation reaction involves reaction of soluble salts to form a precipitate as one of the product.
I belive the answer to your question would be 0
