Answer:
The statement that best describes the trend in first ionization enery of elements on the periodic table is:
It generally decreases down a group because valence electrons are farther from the nucleus.
The first ionization energy measures how difficult is to release an electron from the outermost shell. The higher the ionization energy the more difficult it is to release an electron, the lower the ionication energy the easier to release an electron.
As the atomic number of the atom increases (which is what happens when you go down a group) the furthest the outermost shell of electrons will be (the size of the atoms increases) and so those electrons require less energy to be released, which means that the ionization energy decreases.
Hope it helps!
Answer:
Wavelength (typically measured in nanometers) is the distance between two points in a wave.Frequency (typically measured in Hertz) is the number of waves in a specific time . Frequency and wavelength have both direct and inverse relationships. The crucial difference between frequency and wavelength is that frequency shows the total number of wave oscillations in a given time. As against wavelength specifies the distance between two specific points of a wave.
Explanation:
Frequency is how often something changes per second be it amplitude of a voltage on a wire or be it the bobbing back and forth of a bobblehead. Frequency is how often something moves up and down in a second. If a bobble head moves forward and backward in one second then it has a bobbling frequency of 1 Hertz (Hz). The unit of frequency is Hertz (Hz) or # of cycles or oscillations per second. A wavelength is measured in distance like meters (m). For photons or light or radiowaves the equation is wavelength=speed of light/frequency.
Answer:
Q = 306 kJ
Explanation:
Given that,
Mass, m = 60 kg
Specific heat, c = 1020 J/kg°C
The temperature changes from 20°C to 25°C.
Let Q be the change in thermal energy. The formula for the heat released is given by :
Put all the values,
So, 306 kJ is the change in thermal energy.
It can be done. Normally the boiling point of water is 100°C. It will boil at temperature greater than 100°C more quickly. Water can be boiled at 95°C but for that the atmospheric pressure of the water should be decreased which will decrease the boiling point of water.
<h3>
Concept :</h3>
To boil water at 95°C, decrease the atmospheric pressure.
At 105°C, the water will be boiling quickly than normal at 100°C.
Answer:
[NaOH} = 0.4 M
Explanation:
In a reaction of neutralization, we determine the equivalence point of the titration. In this case, we have a strong base and a strong acid.
(H₂SO₄, is considered strong, but the first deprotonation is weak)
2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
As we have 2 protons in the acid, we need 2 OH⁻ from the base to form 2 molecules of water.
In the equivalence point we know mmoles of base = mmoles of acid
Let's finish the excersise with the formula
25 mL . M NaOH = 28.2 mL . 0.355M
M NaOH = (28.2 mL . 0.355M) / 25 mL → 0.400
