Answer:
2-
Explanation:
For an element to be stable, it must follow the octet rule: an atom will gain, lose or share electrons until its valence shell is complete with 8 electrons.
An element with the valence electron configuration ns²np⁴ has 6 (2+4) electrons in its valence shell. Thus, in order to fulfill the octet, it will gain 2 electrons. As a consequence, it will form an anion with charge 2-.
Answer:
Solving by the method of exponential growth.
bacteria = 2
after one hr = 2² = 4
after 2nd hr = 2³ = 8
after 3rd hr = 2⁴ = 16
after 4th hr = 2⁵ = 32
Answer:
No photoelectric effect is observed for Mercury.
Explanation:
From E= hf
h= Plank's constant
f= frequency of incident light
Threshold Frequency of mercury= 435×10^3/ 6.6×10^-34 × 6.02×10^23
f= 11×10^14 Hz
The highest frequency of visible light is 7.5×10^14. This is clearly less than the threshold frequency of mercury hence no electron is emitted from the mercury surface
There are a number of
ways to express concentration of a solution. This includes molarity. Molarity
is expressed as the number of moles of solute per volume of the solution. The
concentration of the solution is calculated as follows:
<span> </span><span>Molarity = 15.5 g NaOH (1 mol NaOH / 40 g NaOH) / .250 L
solution</span>
<span>Molarity = 1.55 M</span>
None of the above I believe it is what can form a tornado??
