The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as system's mass cannot change, so quantity cannot be added nor removed. Hence, the quantity of mass is conserved over time.
The law implies that mass can neither be created nor destroyed, although it may be rearranged in space, or the entities associated with it may be changed in form. For example, in chemical reactions, the mass of the chemical components before the reaction is equal to the mass of the components after the reaction. Thus, during any chemical reaction and low-energy thermodynamic processes in an isolated system, the total mass of the reactants, or starting materials, must be equal to the mass of the products.
According to the Law of Conservation, all atoms of the reactant(s) must equal the atoms of the product(s).
As a result, we need to balance chemical equations. We do this by adding in coefficients to the reactants and/or products. The compound(s) itself/themselves DOES NOT CHANGE.
1) ₁₄Si 1s²2s²2p⁶3s²3p².
Principal quantum number (n=3) have four electrons (3s²3p²).
2) ₁₉K 1s²2s²2p⁶3s²3p⁶4s¹.
Azimuthal quantum number (l=o) have seven electrons (1s²2s²3s²4s¹).
3) ₈₀Hg [Xe] 4f¹⁴5d¹⁰6s².
Principal quantum number (n=4) have thirty-two electrons (4s²4p⁶4d¹⁰4f¹⁴).
The principal quantum number<span> is one of four </span>quantum numbers<span> which are assigned to each electron in an </span>atom<span> to describe that electron's state.</span>
The azimuthal quantum number<span> is a </span>quantum number<span> for an </span>atomic orbital<span> that determines its </span>orbital angular momentum<span> and describes the shape of the orbital. </span>
Answer:
- <em>The solution expected to contain the greatest number of solute particles is: </em><u>A) 1 L of 1.0 M NaCl</u>
Explanation:
The number of particles is calculated as:
a) <u>For Ionic compounds</u>:
- molarity × volume in liters × number of ions per unit formula.
b) <u>For covalent compounds</u>:
- molarity × volume in liters
The difference is a factor which is the number of particles resulting from the dissociation or ionization of one mole of the ionic compound.
So, calling M the molarity, you can write:
- # of particles = M × liters × factor
This table show the calculations for the four solutions from the list of choices:
Compound kind Particles in solution Molarity # of particles
(dissociation) (M) in 1 liter
A) NaCl ionic ions Na⁺ and Cl⁻ 1.0 1.0 × 1 × 2 = 2
B) NaCl ionic ions Na⁺ anc Cl⁻ 0.5 0.5 × 1 × 2 = 1
C) Glucose covalent molecules 0.5 0.5 × 1 × 1 = 0.5
D) Glucose covalent molecules 1.0 1.0 × 1 × 1 = 1
Therefore, the rank in increasing number of particles is for the list of solutions given is: C < B = D < A, which means that the solution expected to contain the greatest number of solute particles is the solution A) 1 L of 1.0 M NaCl.
Some elements have isotopes which have a different number of neutrons, and this means they have different masses.
This is the electron configuration of neptunium:
<span>Rn 5f4 6d1 7s2
</span>or, if you want to complicate:
<span>1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f4 6d1
</span>Since there are 93 electrons, they make up 5f4 altogether.
