Answer:
the third one, measured or observed without changing the identity and composition of matter. because physical property does not under go any change but can be put back.
Its pH is constant which is neither acid or base
Answer:1.123 x 10^-31cm
Explanation:
mass of humming bird= 11.0g
speed= 1.20x10^2mph
but I mile = 1.6m
1km=1000
I mile = 1.6x10^3m
1.20x10^2mph= 1.6x10^3m /1mile x at 1.20 x 10^2
=1.932 x10^5m
recall that
1 hr= 60 min
1 min=60 secs, 1hr=3600s
Speed = distance/ time
=1.932 x10^5 / 3600= 5.366 x 10 ^1 m/s
m= a 11.0g= 11.0 x 10^-3kg
h=6.626*10^-34 (kg*m^2)/s
Wavelength = h/mu
= 6.626*10^-34/(11 x 10^-3 x 5.366x 10^1)
6.63x10^-34/ 590.26x 10 ^-3= 1.123 x10^-33m
but 1m = 100cm
1.123 x 10 ^-33 x 100 = 1.123 x 10^-31cm
de broglie wavelength of humming bird = 1.123 x 10 ^-31cm
A solid is hard and the molecules are packed together, a liquid can move around freely because the molecules aren't as packed together :)