Answer:
<h3><em>
Please make sure to re-write this on your own so your teacher doesn't think that your cheating!</em></h3>
Explanation:
A neutral atom will have the same number of electrons does protons. Since it has 4 protons, it must have an atomic number of 4. (That will make it beryllium.) Since it has 4 protons and 5 neutrons, it has a mass number of 9.
So the answer is 9
6.069 grams is the mass of hydrogen formed when 27 g of aluminum reacts with excess hydrochloric acid.
Explanation:
Balanced equation for the reaction:
2 Al + 6 HCl → 2 AlCl₃ + 3 H₂
data given:
mass of aluminum = 27 grams
atomic mass of one mole of aluminum = 26.89 grams/mole
formula to calculate number of moles:
number of moles = 
number of moles = 
= 1.004 moles of aluminum will react
from the balanced equation:
2 moles of Al reacted to form 3 moles of H2
1.004 moles of Al will produce x moles of H2
= 
x = 3.012 moles of H2 will be formed.
mass will be calculated as number of moles multiplied by atomic weight
mass of 3.012 moles of hydrogen ?(atomic weight of one mole H2 = 2.015 grams)
= 3.012 x 2.015
= 6.069 grams of H2 will be formed.
Answer:
C. 1 cubic foot of loose sand
Explanation:
For many objects having equal volume , surface area will be maximum
of the object which has spherical shape .
But when a sphere is broken into tiny small spheres , total surface area of all the small spheres will be more than surface area of big sphere .
Hence among the given option , surface area of loose sand will have greatest surface area . Loose sand is equivalent to small spheres .