<span>The first method to determine the chemical composition of a substance in space was using light. By determining red shift in the observed spectrum of light they could determine the elements they were observing. Different elements change the way light behaves and from this scientists can determine the makeup of things such as stars and nebulas.</span>
Answer : The Lewis-dot structure of
is shown below.
Explanation :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is, 
As we know that rubidium has '1' valence electrons, iodine has '7' valence electrons and oxygen has '6' valence electrons.
Therefore, the total number of valence electrons in
= 1 + 7 + 2(6) = 20
As we know that
is an ionic compound because it is formed by the transfer of electron takes place from metal to non-metal element.
Answer:
60 J
Explanation:
The law of conservation of energy states that energy is neither created nor destroyed, just converted into different forms. This means the total mechanical energy of the object at point A will be the same as the total mechanical energy at point B, and the question tells us the total of that mechanical energy is 150 J. Note we are assuming no energy is lost from the system as heat.
At point B, if the potential energy is 90 J, the remainder of the 150 J total must be kinetic energy. KE = 150 J - 90 J = 60 J.
Answer: Communicable diseases, abuse gunshot wounds and forensic medicine
Explanation:
Molar mass C6H12O6 = 12 x 6 + 1 x 12 + 16 x 6 = 180 g/mol
1 mole ------------ 180 g
( moles ) --------- 843.211 g
moles = 843.211 x 1 / 180
moles = 843.211 / 180
= 4,684 moles of C6H12O6