Answer:
The answer to your question is: 20
Explanation:
Atomic number is the number of proton and atom has. Each element has a specific number of protons, if the number of protons change, then this is a new element.
Mass number is the number of protons and neutrons and atom has.
Mass number = protons + neutrons
Data
Number of protons = ?
Atomic number = 20
Then,
atomic number = number of protons = 20
Answer:All of the elements in a period have the same number of atomic orbitals. For example, every element in the top row (the first period) has one orbital for its electrons. All of the elements in the second row (the second period) have two orbitals for their electrons.Explanation:
Main Answer:
Given speed of spaceship v = 0.8c = 0.8 * 3 x 10^8 m/s
Speed of spaceship v = 2.4 x 10^8 m/s
Distance need to be travelled d = 4.3 light years
we know that 1 light year = 9.461 x 10^15 m
Distance need to be travelled d = 4.3 x 9.461 x 10^15
d = 40.6823 x 10^15 m
Time taken for the trip would elapse on a clock on board the spaceship
t = distance/ velocity
t = 40.6823 x 10^15 / 2.4 x 10^8
t = 16.95 x 10^7 sec
t = 4.71 x 10^4 hours
Explanation:
What is light year?
Light year is defined as the distance travelled by the light in one year. In a year, light travels through 300000 km per sec in the interstellar space.
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