## sara12345 3 years ago as we move from left to right across a period how density changes

1. sara12345

1. increases 2. decreases 3. remains constant 4. no particular trend

2. UnkleRhaukus

density is mass per unit volume

3. .Sam.

Density increases. Atomic radius decreases from left to right across a period because: 1) Electrons are being "added" into the same shell, (you know that the shell number doesn't increase across a period) 2) The proton number and number of electrons increases across a period, this causes greater attractive force between positive and negative charges, resulting in decrease in atomic radius as mass increases, therefore greater density.

4. sara12345

mass increases but radius decreases since d = m/V density increases i get it thank you very much !

5. UnkleRhaukus

i do not agree with options 1,2,3,4

6. sara12345

but the right side we have gases but here i think they're asking only for atom i hope, not the molecule level

7. sara12345

why

8. UnkleRhaukus
9. sara12345

oh it shows left and right groups have least density

10. sara12345

some trend still exists, as we move from left to right, s->p->d, upto the last group in d block, the density is increasing

11. sara12345

looks non-metals have less density again breaking the general increasing density trend