Answer:
Density = 11.4 g/cm³
Explanation:
Given data:
Density of lead = ?
Height of lead bar = 0.500 cm
Width of lead bar = 1.55 cm
Length of lead bar = 25.00 cm
Mass of lead bar = 220.9 g
Solution:
Density = mass/ volume
Volume of bar = length × width × height
Volume of bar = 25.00 cm × 1.55 cm × 0.500 cm
Volume of bar = 19.4 cm³
Density of bar:
Density = 220.9 g/ 19.4 cm³
Density = 11.4 g/cm³
Answer:
Radioactive isotopes ranging from 11O to 26O have also been characterized, all short-lived. The longest-lived radioisotope is 15O with a half-life of 122.24 seconds, while the shortest-lived isotope is 12O with a half-life of 580(30)×10−24 seconds (the half-life of the unbound 11O is still unknown).
Answer:
V = 2600ms⁻¹
Explanation:
Given parameters:
Wavelength(λ) = 13meters
Period (T) = 0.005s
Period(T) is the time it takes for a full cycle of vibration to pass through. It's unit is in seconds (s)
The Velocity of waves is expressed as:
V = fλ
Where f = frequency(s⁻¹)
Frequency of a wave is the number of waves that passes through a point per unit time
f = 1/T
Where T is the period
We can therefore express Velocity of waves as a function of period
V = λ/T
Inputing the parameters, we have:
V = 13m / 0.005s
V = 2600ms⁻¹
2 shells because if you do the electronic configuration:
2,7 which adds up to 9
7 stands for the group it in and it also stands for how many electrons are in the outer shell.
the amount of spaces stands for which period its in therefore it in period 2