Methyl orange shows red color in acidic medium and yellow color in basic medium. Because it changes color at the pKa of a mid strength acid, it is usually used in titration for acids. Unlike a universal indicator, methyl orange does not have a full spectrum of color change, but it has a sharp end point.
Answer:
0.4694 moles of CrCl₃
Explanation:
The balanced equation is:
Cr₂O₃(s) + 3CCl₄(l) → 2CrCl₃(s) + 3COCl₂(aq)
The stoichiometry of the equation is how much moles of the substances must react to form the products, and it's represented by the coefficients of the balanced equation. So, 1 mol of Cr₂O₃ must react with 3 moles of CCl₄ to form 2 moles of CrCl₃ and 3 moles of COCl₂.
The stoichiometry calculus must be on a moles basis. The compounds of interest are Cr₂O₃ and CrCl₃. The molar masses of the elements are:
MCr = 52 g/mol
MCl = 35.5 g/mol
MO = 16 g/mol
So, the molar mass of the Cr₂O₃ is = 2x52 + 3x35.5 = 210.5 g/mol.
The number of moles is the mass divided by the molar mass, so:
n = 49.4/210.5 = 0.2347 mol of Cr₂O₃.
For the stoichiometry:
1 mol of Cr₂O₃ ------------------- 2 moles of CrCl₃
0.2347 mol of Cr₂O₃----------- x
By a simple direct three rule:
x = 0.4694 moles of CrCl₃
Answer:
Most common insulation materials work by slowing conductive heat flow and--to a lesser extent--convective heat flow. Radiant barriers and reflective insulation systems work by reducing radiant heat gain. To be effective, the reflective surface must face an air space.
Explanation:
To be effective, the reflective surface must face an air space.
To be able to write correctly the equilibrium expression of a reaction, we need to know the balanced reaction and the phases of the substances in the reaction. When substances are solid, pure liquid they are not included in the expression. We do as follows:
<span>4KO2(s) + 2H2O(g) = 4KOH(s) + 3O2(g)
K = [O2]^3 / [H2O]^2</span>
<h3>
Answer:</h3>
9 mol H₂O
<h3>
General Formulas and Concepts:</h3>
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Chemistry</u>
<u>Atomic Structure</u>
- Reading a Periodic Table
- Moles
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
<u>Stoichiometry</u>
- Using Dimensional Analysis
- Analyzing reactions RxN
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[RxN - Balanced] 6H₂ + O₂ → 3H₂O
[Given] 18 mol H₂
[Solve] mol H₂O
<u>Step 2: Identify Conversions</u>
[RxN] 6 mol H₂ → 3 mol H₂O
<u>Step 3: Stoich</u>
- [DA] Set up conversion:
- [DA] Simplify:
- [DA] Divide [Cancel out units]:
