x21 +ANSWER
(i) Ne-22
(ii)1s2s22p6
(iii)21.3
An element X exists in three forms A, B and C in the ratio 1:2:3. If C has 10 protons and the number of neutrons in A, B and C are 10, 11 and 12 respectively,Give the following:(i) Representation of form C of the element X(ii) Electronic configuration of form B of the element(iii) Calculate the average atomic mass.
(i)C has 10 protons and 12 neutrons so a mass of 10 +12 =22
element 10 is Neon (Ne) so this isotope is Ne-22
(ii) they all have the sane atomic number so the same number of electrons
with an electronic structure of 1s2s22p6
(iii) A weighs 20, B weighs 21, C weighs 22
the ratio is 1:2:3
weighted average weight is therefor
(1X20 +2X21 +3X22)/6 =21.3
Answer:
Scandium
Explanation:
Mendeleev played an important role in the development of the modern periodic table. His periodic table was filled with gaps. He said that these gaps were elements that were yet to be discovered. He rightly predicted many elements which have now been discovered and fitted in their proper places in the periodic table.
He used the prefix ''eka'' to refer to elements whose properties were alike but were yet to be discovered at that time.
The compound named ekaboron which he predicted to have an atomic weight between 65 (zinc) and 75 (arsenic) with a valence similar to aluminum was later discovered in 1879 and properly named scandium.
The textbook Would most likely have more gravitational potential energy because it is heavier. Things that are heavier have a larger gravitational pull and are pulled to the earth faster
Answer:
2.2 x 10²² molecules.
Explanation:
- Firstly, we need to calculate the no. of moles in (6.0 g) sodium phosphate:
<em>no. of moles = mass/molar mass </em>= (6.0 g)/(163.94 g/mol) = <em>0.0366 mol.</em>
- <em>It is known that every mole of a molecule contains Avogadro's number (6.022 x 10²³) of molecules.</em>
<em />
<u><em>using cross multiplication:</em></u>
1.0 mole of sodium phosphate contains → 6.022 x 10²³ molecules.
0.0366 mole of sodium phosphate contains → ??? molecules.
<em>∴ The no. of molecules in 6.0 g of sodium phosphate</em> = (6.022 x 10²³ molecules)(0.0366 mole)/(1.0 mole) = <em>2.2 x 10²² molecules.</em>
Answer:
Explanation:
The Erosion in the Colorado Rookies Scenario that record a ready rain were more than the other scenario in the same area with just a drizzle. The Erosion is much in the Colorado Rockies Scenario that record a steady rain because the volume of the rivers has goes up compare to that of the Scenario with just a drizzle. As a result of the increased in the amount of the rivers bank that is flowing, the river flows more faster which helps in the transportation of the sediments or Erodes.
