Answer: D. Sends small electrical impulses to the heart, causing it to beat more
Explanation: A pacemaker is implanted in the chest and helps to treat abnormal heart rhythms especially those causing your heart to skip beats or beat too slow.
Here is your answer
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REASON:
Elements which have 4 valence electrons are generally metalloids.
The metalloids show the properties of both metals and non-metals.
We know that,
no. of protons= Atomic number
So,
Atomic no.= 32
Hence,
The element is Germanium which is a metalloid with 4 valence electrons and has 32 protons in nucleus of each atom because it has atomic no. 32
HOPE IT IS USEFUL
Answer: No charge (0)
Explanation:
The atom has a proton of 22 and electron number of 19. This means the element has lost 3 electrons. Therefore, the net charge is +3.
So, if this atom gains 3 more electrons, the net charge would be zero (neutral).
The total number of electron would now be 22 which is the same as the proton number.
This implies the atom is now in an unreacted state or ground state.
Mg+HCl -> MgCl2+H2
So, Hydrogen gas.