Answer: Option (D) is the correct answer.
Explanation:
Valence shell is the shell present on the outermost core of an atom and electrons present in the valence shell are known as valence electrons.
If an atom has completely filled valence shell then it means the atom is not reactive in nature because it is already stable.
But when an atom has less than eight electrons in its valence shell then it means to attain stability the atom will readily attract electrons towards itself.
As the given element 1 has 8 electrons in its valence shell. Hence, it is not reactive in nature but element 2 has 6 valence electrons. So, in order to attain stability element 2 will readily attract 2 electrons from a donor atom.
Thus, we can conclude that element 2 is more reactive because it does not have a full valence shell, so it will attract electrons.
Answer is: <span>No, because she did not stop adding base once the color changed.
</span>The endpoint<span> is the point at which the indicator changes colour in a colourimetric </span>titration and that is point when titration must stop or results are going to be wrong, because t<span>he </span><span>equivalence point of titration is not measured right.</span>
B - Sediment . Many layers of sediment slowly built up into a rock which turn into a fossil .
The correct answer for the question that is being presented above is this one: "B) Temperature."
Here are the following choices:
A) all of these measurements are needed
B) Temperature
C) Molar Mass
D) Pressure
E) Mass
<span>The amount of
protons is equal to the number of electrons of a chemical element. The atomic
number of an element also determines the number of the protons it contains.
The number of protons is also the same number of electrons. Protons are positively charged, electrons are
negatively charged. To get the number of neutrons, all you need is to deduct
the number of the atomic mass or mass number from the atomic number. Potassium has 19
protons, therefore has 19 electrons as well. The atomic mass of Potassium is
39. So, the number of neutrons Potassium has is 20. </span>
Potassium
Atomic
number: 19
Protons: 19
Electrons: 19
Atomic Mass:
39
Neutron: 20
Nitrogen
Atomic
number: 7
Protons: 7
Electrons: 7
Atomic Mass:
14.007
Neutrons: 7
Oxygen
Atomic
Number: 8
Protons: 8
Electrons: 8
Atomic Mass:
15.99
Neutrons: 8
