Answer:
Explanation: obtain and use energy, make new cells, exchange materials, eliminate wastes
Answer:
= 0.014 g of BaCO3
Explanation:
Let x = mol/L of BaCO3 that dissolve.
This will give;
x mol/L Ba2+ and x mol/L CO32-
But;
Ksp = 5.1x10^-9.
Therefore;
Ksp = 5.1 x 10^-9 = (x)(x)
Thus;
x = molar solubility
= √ (5.1 x 10^-9)
= 7.1 x 10^-5 M
Therefore;
Mass BaCO3 = 7.1 x 10^-5 M x 1 L x 197.34 g/mol
= 0.014 g
Answer:
Explanation:
There are seven periods in the periodic table, with each one beginning at the far left. A new period begins when a new principal energy level begins filling with electrons. Period 1 has only two elements (hydrogen and helium), while periods 2 and 3 have 8 elements. Periods 4 and 5 have 18 elements.
Answer:
1.146 x 10⁴ year.
Explanation:
- The decay of carbon-14 is a first order reaction.
- The rate constant of the reaction (k) in a first order reaction = ln (2)/half-life = 0.693/(5730 year) = 1.21 x 10⁻⁴ year⁻¹.
- The integration law of a first order reaction is:
<em>kt = ln [A₀]/[A]</em>
<em></em>
k is the rate constant = 1.21 x 10⁻⁴ year⁻¹.
t is the time = ??? years.
[A₀] is the initial percentage of carbon-14 = 100.0 %.
[A] is the remaining percentage of carbon-14 = 1/4[A₀] = 25.0 %.
∵ kt = ln [Ao]/[A]
∴ (1.21 x 10⁻⁴ year⁻¹)(t) = ln (100.0%)/[25.0 %]
(1.21 x 10⁻⁴ year⁻¹)(t) = 1.386.
∴ <em>t </em>= 1.386/
(1.21 x 10⁻⁴ year⁻¹) = <em>1.146 x 10⁴ year.</em>
