Average Atomic Mass

100 - 72.15 = 27.85 [(72.15 × 84.9118) + (27.85 × 86.9092)] ÷ 100 = 85.47 amu.

A certain element has 2 isotopes; one isotope has an abundance of 72.15% has a mass of 84.9118 amu. The other has a mass of 86.9092 amu. Calculate the average atomic mass for this element.

E=hv E=(6.626x10^-34)(2.68x10^6) E=1.78x10^-27

A photon has a frequency of 2.68x10^6 Hz. Calculate its energy.

20.17 amu

Neon has 3 different isotopes; 90.51% have a mass of 19.992 amu, 0.27% have a mass of 20.994, and 9.22% have a mass of 21.991. What is the average atomic mass of Neon?

100 - 75.771 = 24.229 [(75.771 × 34.96885) + (24.229 × 36.9659)] ÷ 100 = 35.45 amu.

Of all chlorine atoms, 75.771% are chlorine-35, which have a mass of 34.96885 amu. All other chlorine atoms are chlorine-37 and these have a mass of 36.9659. What is chlorine's average atomic mass?

[(24.1 × 75.23) + (48.7 × 74.61) + (27.2 × 75.2)] ÷ 100 = 74.9199 amu. The element is Arsenic.

An element exists as 3 different isotopes; 24.1% have a mass of 75.23 amu, 48.7% have a mass of 74.61, and 27.2% have a mass of 75.2. What is the average atomic mass? Which element is it?

[(4.35 × 49.9461) + (83.79 × 51.9405) + (2.36 × 53.9389) + (9.5 × 52.9407)] ÷ 100 = 51.99592484 amu. The element is Chromium

An element exists as 4 different isotopes; 4.35% have a mass of 49.9461 amu, 83.79% have a mass of 51.9405, 2.36% have a mass of 53.9389, and 9.5% have a mass of 52.9407. What is the average atomic mass? Which element is it?

The most abundant is 40 because calcium's average mass is 40.078

Calcium has 3 different isotopes; one has a mass of 35 amu, another has a mass of 40, and another has a mass of 41. Which isotope is the most abundant of the three?

v=7.5x10^14Hz E=4.97x10^-19J

Calculate the energy and frequency of blue light that has a wavelength of 400nm.

E=2.92x10^-19 J V=4.4x10^14 Hz

Calculate the energy and frequency of red light having a wavelength of 6.8x10^-5cm

λ=2x10^-7 E=9.95x10^-19

Calculate the energy and wavelength of light that has a frequency of 1.5x10^15 Hz

Cl-35: 18n 17p Cl-37: 20n 17p

Chlorine-35 is one isotope of chlorine (35 is the mass number). Chlorine-37 is another isotope of Chlorine. How many protons and how many neutrons are in each isotope of chlorine?

mx10^-9 = nm

M = ?nm

[(4.35 × 39.946) + (83.79 × 41.941) + (2.36 × 43.939) + (9.5 × 42.941)] ÷ 100 = 41.9963703 amu.

Several isotopes of a certain atom 'x' exist. 4.35% of all x atoms have a mass of 39.946 amu, 83.79% have a mass of 41.941, 9.5% have a mass of 42.941, and 2.36% have a mass of 43.939. What id the average atomic mass of atom x?

5.77x10^14 Hz

The wavelength of green light from a traffic signal is centred at 5.2x10^-5cm. Calculate the frequency.