The elements are Krypton and Xenon
Answer:
Isotope (ahy-suh-tohps)are atom with the same number of protons but differing numbers of neutrons.In other words,isotopes have different atomic weights.Isotopes are different forms of a single element.
Explanation:
Making repeated separations of the various substances in the pitchblende, Marie and Pierre used the Curie electrometer to identify the most radioactive fractions. They thus discovered that two fractions, one containing mostly bismuth and the other containing mostly barium, were strongly radioactive.
<h3>What was surprising about pitchblende?</h3>
Since it was no longer appropriate to call them “uranic rays,” Marie proposed a new name: “radioactivity.”
Even more surprising, Marie next found that a uranium ore called pitchblende contained two powerfully radioactive new elements: polonium, which she named for her native Poland, and radium.
<h3>Why is radium more radioactive than uranium?</h3>
It is 2.7 million times more radioactive than the same molar amount of natural uranium (mostly uranium-238), due to its proportionally shorter half-life.
Learn more about highly radioactive elements here:
<h3>
brainly.com/question/10257016</h3><h3 /><h3>#SPJ4</h3>
Answer:
<em>21.14 K</em>
Explanation:
<em>We know the Ideal Gas Equation is :-</em>
<em>PV = nRT</em>
<em>=> T = PV/nR</em>
<em>=> T = 6.5 x 20 / 7.5 x 0.082</em>
<em>=> T = 130 / 6.15</em>
<em>=> T = 21.14 K</em>
The equilibrium constant (K) : 11.85
<h3>Further explanation</h3>
Given
Reaction
N₂(g) + 3H₂(g) ⇒ 2NH₃(g)
Required
K(equilibrium constant)
Solution
The equilibrium constant (K) is the value of the concentration product in the equilibrium
The equilibrium constant based on concentration (K) in a reaction
pA + qB -----> mC + nD
![\tt K=\dfrac{[C]^m[D]^n}{[A]^p[B]^q}](https://tex.z-dn.net/?f=%5Ctt%20K%3D%5Cdfrac%7B%5BC%5D%5Em%5BD%5D%5En%7D%7B%5BA%5D%5Ep%5BB%5D%5Eq%7D)
For the reaction above :
![\tt K=\dfrac{[NH_3]^2}{[N_2][H_2]^3}\\\\K=\dfrac{0.1^2}{0.25\times 0.15^3}\\\\K=11.85](https://tex.z-dn.net/?f=%5Ctt%20K%3D%5Cdfrac%7B%5BNH_3%5D%5E2%7D%7B%5BN_2%5D%5BH_2%5D%5E3%7D%5C%5C%5C%5CK%3D%5Cdfrac%7B0.1%5E2%7D%7B0.25%5Ctimes%200.15%5E3%7D%5C%5C%5C%5CK%3D11.85)
