Answer is: beryllium-10.
The diagram shows that atom has 4 protons, 5 neutrons and 2 valence electrons.
Atomic number is the number of protons, which is characteristic of a chemical element, beryllium (Be) is an element with atomic number 4.
Two valence electrons means that atom is from 2. group of periodic table, only beryllium is from that group; sodium (1. group), boron (13. group) and carbon (14. group).
Beryllium-10 has 6 neutrons, so it is isotope (different number of neutrons or mass number).
Answer:
sugar and oxygen
Explanation:
sugar (glucose) and oxygen
All elements are pure substances.
Answer:
The speed of the 60.0 kg skater should be 0.281 m/s
Explanation:
<u>Step 1: </u>Data given
Mass of skater 1 = 45.0 kg
speed of skater 1 = 0.375 m/s
Mass of skater 2 = 60.0 kg
<u>Step 2:</u> Calculate the speed of skater 2
To solve this problem, we will use 'Conservation of momenton'. This means the momentum before the push equals the momentum after.
momentum p = m*v
Momentum p(before) = momentum p(after)
m1*v1 = m2 * v2
⇒ with m1 = mass of skater 1 = 45.0 kg
⇒ with v1 = the velocity of skater 1 = 0.375 m/s
⇒ with m2 = the mass of skater 2 = 60.0 kg
⇒ with v2 = the velocity of skater 2 = TO BE DETERMINED
45.0 * 0.375 = 60.0 * v2
v2 = (45.0*0.375)/60
v2 = 0.281 m/s
The speed of the 60.0 kg skater should be 0.281 m/s
It can be predicted from the location on the periodic table.
