Answer:
The chemist would require to use 43.43 grams.
Explanation:
In order to solve this problem we need to know<u> how much do 0.550 moles of selenium weigh</u>. To do that we use selenium's<em> molar mass </em>and multiply it by the given number of moles:
- 0.550 mol * 78.96 g/mol = 43.43 g
The chemist would require to use 43.43 grams.
D. The particles are tightly packed together
Answer:Nuclear binding energy is the energy needed to separate nuclear particles
The strong nuclear force holds an atom’s protons and neutrons together
Nuclear binding energy can be calculated using E=mc2
Explanation:
Answer : The incorrect option is, The most of the mass of the atom comes from the electron cloud.
Explanation :
There are three basic particles of an atom which are neutrons, protons and electrons.
The nucleus which is present in the center of an atom that contains the neutrons and the protons. The protons are positively charged and neutrons has no charge.
The outer region of an atom contains the electrons and the electrons are negatively charged.
As per given options, the statement which is the most of the mass of the atom comes from the electron cloud is incorrect statement because the most of the mass comes from the nucleus in which protons and neutrons are present.
The ionization energy for a hydrogen atom in the n = 2 state is 328 kJ·mol⁻¹.
The <em>first ionization energy</em> of hydrogen is 1312.0 kJ·mol⁻¹.
Thus, H atoms in the <em>n</em> = 1 state have an energy of -1312.0 kJ·mol⁻¹ and an energy of 0 when <em>n</em> = ∞.
According to Bohr, Eₙ = k/<em>n</em>².
If <em>n</em> = 1, E₁= k/1² = k = -1312.0 kJ·mol⁻¹.
If <em>n</em> = 2, E₂ = k/2² = k/4 = (-1312.0 kJ·mol⁻¹)/4 = -328 kJ·mol⁻¹
∴ The ionization energy from <em>n</em> = 2 is 328 kJ·mol⁻¹
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