Answer:
2s²2p⁴
Explanation:
Oxygen is an element on the periodic table with a total of 8 electrons. It's electronic configuration is given as 2,6.
Using the orbital notation we write as 1s²2s²2p⁴
Also, the valence electrons are the electrons in the outermost shell of an atom. These electrons mostly determine the chemical properties of an atom.
Oxygen has a total of 6 electrons in its outermost shell and it is given as 2s²2p⁴
The question is incomplete, the complete question is;
The table above summarizes data given to a student to evaluate the type of change that took place when substance X was mixed with water. The student claimed that the data did not provide enough evidence to determine whether a chemical or physical change took place and that additional tests were needed. Which of the following identifies the best way to gather evidence to support the type of change that occurred when water and Xwere mixed?
A. Measuring the melting point of the mixture of water and X
B. Adding another substance to the mixture of water and X to see whether a solid forms
C Measuring and comparing the masses of the water, X, and the mixture of water and X
D Measuring the electrical conductivities of X and the mixture of water and X
Answer:
D Measuring the electrical conductivities of X and the mixture of water and X
Explanation:
Unfortunately, I am unable to reproduce the table here. However, from the table, the temperature of the of the mixture of the solid X and water was 101.6°C. This is above the boiling point of water and way below the temperature of the solid X.
This goes a long way to suggest that there was some kind of interaction between the water and X which accounted for the observed temperature of the system of X in water.
The only way we can be able to confirm if X actually dissolved in water is to measure the conductivity of the water. dissolved solids increase the conductivity of water.
Answer:
Explanation:
specific heat of granite s = .79 J / g / k
let the mass of granite = m
heat lost by granite = heat gained by water
heat lost = mass x specific heat x drop in temperature
= m x .79 x (80 - 20.45)
heat gained by water
= 3000 x 4.186 x (20.45- 20)
heat lost by granite = heat gained by water
m x .79 x 59.55 = 3000 x 4.186 x .45
m = 120.12 g .
The formula to be used for this problem is as follows:
E = hc/λ, where h is the Planck's constant, c is the speed of light and λ is the wavelength. Also 1 aJ = 10⁻¹⁸ J
0.696×10⁻¹⁸ = (6.62607004×10⁻³⁴ m²·kg/s)(3×10⁸ m/s)/λ
Solving for λ,
λ = 2.656×10⁻⁷ m or <em>0.022656 nm</em>