If the neutral atom of an element has only 5 valence electrons it must be in which group? 1. viia 2. va 3. ivb 4. via 5. iva 6. iiia

2. VA

Explanation:

The valency electron or outer electron of a neutral atom of an element determines the group at which an element belong. The electronic configuration of an atom that have valency of 5 can be represented as 2 5 ,  2 8 5 etc.

The electronic configuration 2 5 represent Nitrogen atom while 2 8 5 represent phosphorus atom. The valency 5 depicts the element belongs to group 5A(VA).

This means atoms of valency electron of 3 belong to group IIIA, valency electrons of 4 belongs to group IVA, valency electron of 6 belong to group VIA  and valency electrons of  7 belong to group VIIA.  

diameter is decreased by factor 0.91

Explanation:

As we know by the equation of trajectory

here as per first given situation we know that

x = 36.9 m

y = 8.85 m

now from above equation we have

now similarly after nozzle is adjusted we have

y = 17.9 m

x = 36.9 m

now again from equation we have

Now by equation of continuity we can find the change in diameter

as we know that

now we have

so we have

so diameter is decreased by factor of 0.91