Answer:
Forumula
XOH + HY = XY + H2O
Explanation:
Salt formed from: Salt Solution
Strong acid + Strong base Neutral
Strong acid + Weak base Acidic
Weak acid + Strong base Basic
Neutral solution example
NaCl = Sodium chloride
HCl = H+ and Cl-
NaOH = Na+ and OH-
OH- = Strong Base
H+ = Strong Acid
Sodium chloride, formed from neutralization of HCl by NaOH.
NaOH + HCl = NaCl + H2O
NaCl in water is not acidic or basic, since it's ions cannot hydrolyze.
So formula would be XOH + YH = XY + H2O
Balanced chemical reaction: Pb(NO₃)₂ (aq) + 2NaI(aq) → 2PbI₂(s) + 2NaNO₃(aq).
V(Pb(NO₃)₂) = 50 mL ÷ 1000 mL = 0.05 L, volume of solution.
c(Pb(NO₃)₂) = 0.1 mol/L; concentration of solution.
n(Pb(NO₃)₂) = c(Pb(NO₃)₂) · V(Pb(NO₃)₂).
n(Pb(NO₃)₂) = 0.1 mol/L · 0.05 L.
n(Pb(NO₃)₂) = 0.005 mol.
n(NaI) = c(NaI) · V(NaI).
n(NaI) = 0.1 mol/L · 0.05 L.
n(NaI) = 0.005 mol; amount of substance.
From chemical reaction: n(Pb(NO₃)₂) : n(NaI) = 1 : 2.
n(Pb(NO₃)₂) = 0.005 mol ÷ 2.
n(Pb(NO₃)₂) = 0.0025 mol; number of moles Pb(NO₃)₂ used.
n(NaI) = 0.005 mol; number of moles NaI used.
The limiting reagent is Pb(NO₃)₂.
n(PbI₂) = 0.005 mol.
m(PbI₂) = n(PbI₂) · M(PbI₂).
m(PbI₂) = 0.005 mol · 461 g/mol.
m(PbI₂) = 2.305 g; the theoretical yield of PbI₂.
You take the grams of CO₂ times Avogadro's number divided by the molar mass.
Answer:
713 nm. It is not visible with the naked eye.
Explanation:
Step 1: Given data
- Energy of light (E): 2.79 × 10⁻¹⁹ J
- Planck's constant (h): 6.63 × 10⁻³⁴ J.s
- Speed of light (c): 3.00 × 10⁸ m/s
Step 2: Calculate the wavelength of the light
We will use the Planck-Einstein equation.
E = h × c / λ
λ = h × c / E
λ = 6.63 × 10⁻³⁴ J.s × 3.00 × 10⁸ m/s / 2.79 × 10⁻¹⁹ J
λ = 7.13 × 10⁻⁷ m
Step 3: Convert "λ" to nm
We will use the relationship 1 m = 10⁹ nm.
7.13 × 10⁻⁷ m × (10⁹ nm/1 m) = 713 nm
This light is not in the 400-700 nm interval so it is not visible with the naked eye.
44. (a) N2O3 (b) SF4 (c) AlCl3 (d) Li2CO3
46. H Br
δ+ δ−
48. The metallic potassium atoms lose one electron and form +1 cations,
and the nonmetallic fluorine atoms gain one electron and form –1 anions.
K → K+
+ e–
19p/19e–
19p/18e–
F + e–
→ F–
9p/9e–
9p/10e–
The ionic bonds are the attractions between K+
cations and F–
anions.
50. See Figure 3.6.
52. (a) covalent…nonmetal-nonmetal (b) ionic…metal-nonmetal
54. (a) all nonmetallic atoms - molecular (b) metal-nonmetal - ionic
56. (a) 7 (b) 4
58. Each of the following answers is based on the assumption that nonmetallic
atoms tend to form covalent bonds in order to get an octet (8) of
electrons around each atom, like the very stable noble gases (other than
helium). Covalent bonds (represented by lines in Lewis structures) and lone
pairs each contribute two electrons to the octet.
(a) oxygen, O
If oxygen atoms form two covalent bonds, they will have an octet of electrons
around them. Water is an example:
H O H
(b) fluorine, F
If fluorine atoms form one covalent bond, they will have an octet of electrons
around them. Hydrogen fluoride, HF, is an example:
H F
(c) carbon, C
If carbon atoms form four covalent bonds, they will have an octet of electrons
around them. Methane, CH4, is an example:
H H
H
H
C
(d) phosphorus, P
If phosphorus atoms form three covalent bonds, they will have an octet
