Answer:
the ans is D... good luck
Answer:
helium, neon, argon,krypton, xenon, and radonoccupying Group 0 (18) of the periodic table. They were long believed to be totally unreactive but compounds of xenon, krypton, and radon are now known.
Answer:
b. They orbit around the Sun in a counterclockwise direction, when viewed from above the ecliptic plane.
Explanation:
All the objects of the solar system revolve around the Sun in a counterclockwise direction. The comet coming from the Oort's cloud will also follow the same kind of orbit. That is why it can't be a property to distinguish an Oort's cloud comet.
All other properties are correct to identify an Oort's cloud comet as the Oort's cloud is a considered a spherical cloud just outside the Solar system.
Answer:
size of insect = wavelength = 16.1 mm
Explanation:
Since the bat can detect the size of small insects which are of size equal to the wavelength of sound in air
So here we can say that the wavelength of sound is the ratio of speed of sound and its frequency
here we know that
speed of sound in air is 536 m/s
frequency of sound is 33.3 kHz
so here we can say
1. The mass number is protons + neutrons = mass number. In this case, we have protons + neutron = 164.The atomic number is simply the number of protons so we have 43 + neutrons = 164. Subtracting 43 from both sides we get neutrons = 121.
2. = 4
3. The number of protons in the nucleus does not equal the number of neutrons.
A=mass number:
Z=atomic number (= number of protons)
N=number of neutrons:
A=Z+N
If the number of protons in the nucleus is equal the number of neutrons , we would have an even mass number; because Z=N=x; then A=x+x=2x (this is always an even number) but 23 is an odd number, therefore the number of protons in the nucleus does not equal the number of neutrons.
