Answer:
chemical reaction are the processes in which new substances with new properties of from are called as chemical reaction ex double displacement reaction
Explanation:
Copper is an element.
An element is a substance that is entirely made from one type of atom.
The average atomic mass of the atom that has the following isotopes in the following abundances: 20 10Z 30% , 19 10Z10% , 18 10Z 60% is 18.7.
<h3>How to calculate average atomic mass?</h3>
The average atomic mass of an isotopic element is the weighted average of the atomic masses of the naturally occurring isotopes of an element.
According to this question, the atom has the following isotopes in the following abundances: 20 10Z [30%] = 30/100 × 20 = 6
19 10Z [10%] = 10/100 × 19 = 1.9
18 10Z [60%] = 60/100 × 18 = 10.8
The sum of these masses is the average atomic mass and is calculated as follows:
6 + 1.9 + 10.8 = 18.7
Therefore, the average atomic mass of the atom that has the following isotopes in the following abundances: 20 10Z 30% , 19 10Z10% , 18 10Z 60% is 18.7.
Learn more about average atomic mass at: brainly.com/question/13753702
#SPJ1
Melting, boiling, and evaporation, in general, are endothermic processes.
Answer:
The sun would appear to move more slowly across Mercury's sky.
Explanation:
This is because, the time it takes to do one spin or revolution on Mercury is 176 days (which is its period), whereas, the time it takes to do one spin or revolution on the Earth is 1 day.
Since the angular speed ω = 2π/T where T = period
So on Mercury, T' = 176days = 176 days × 24 hr/day × 60 min/hr × 60 s/min = 15,206,400 s
So, ω' = 2π/T'
= 2π/15,206,400 s
= 4.132 × 10⁻⁷ rad/s
So on Earth, T" = 1 day = 1 day × 24 hr/day × 60 min/hr × 60 s/min = 86,400 s
So, ω" = 2π/T"
= 2π/86,400 s
= 7.272 × 10⁻⁵ rad/s
Since ω' = 4.132 × 10⁻⁷ rad/s << ω" = 7.272 × 10⁻⁵ rad/s, <u>the sun would appear to move more slowly across Mercury's sky.</u>