Answer:
The average atomic mass of element X is 17.561 u.
Explanation:
Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:
.....(1)
We are given:
Mass of isotope X-17 = 17 u
Percentage abundance of isotope X-17 = 65.20 %
Fractional abundance of isotope 1 = 0.6520
Mass of isotope X-18 = 18 u
Percentage abundance of isotope X-18 = 13.50 %
Fractional abundance of isotope X-18 = 0.1350
Mass of isotope X-19 = 19 u
Percentage abundance of isotope X-19 =21.30%
Fractional abundance of isotope X-19 = 0.2130
Putting values in equation 1, we get:
![\text{Average atomic mass of Z}=\sum[(17 u\times0.6520 )+(18 u\times 0.1350)+(19 u\times 0.2130)]](https://tex.z-dn.net/?f=%5Ctext%7BAverage%20atomic%20mass%20of%20Z%7D%3D%5Csum%5B%2817%20u%5Ctimes0.6520%20%29%2B%2818%20u%5Ctimes%200.1350%29%2B%2819%20u%5Ctimes%200.2130%29%5D)
Answer:
Her answer is not reliable.
Explanation:
Reliability and validity are two major concepts that are used to assess the standard and quality of response/research.
While validity of an instrument is the idea that the instrument measures what it intends to measure, reliability is all about consistency and whether or not results could be replicated.
While your friend's answer may be valid, it can't reliable because of the differences in her response within a short time.
Answer:
1. G.P.E = 24 J
2. center of mass
Explanation:
Given the following data;
Mass = 2kg
Height, h = 1.2m
Acceleration due to gravity = 9.8 N/kg or m/s².
To find the gravitational potential energy;
Gravitational potential energy (GPE) is an energy possessed by an object or body due to its position above the earth.
Mathematically, gravitational potential energy is given by the formula;
Where;
- G.P.E represents potential energy measured in Joules.
- m represents the mass of an object.
- g represents acceleration due to gravity measured in meters per seconds square.
- h represents the height measured in meters.
Substituting into the formula, we have;
G.P.E = 23.52 to 2 S.F = 24 Joules.
Translation kinetic energy is defined as the energy of a system due to the motion of the system’s center of mass. The center of mass is typically where the mass of the object or particle is concentrated.
I'm probably going to have to say C. E as it seems the steepest right around there. If I'm wrong on that, it has to be B. B
Solar cells are made out of silicon wafers. These are made out of the element silicon, a hard and brittle crystalline solid that is the second most abundant element in the Earth's crust after oxygen. If you're at the beach and see shiny black specks in the sand, that's silicon.
Hope this helps!
Please give brainliest!
