5. Suppose the efficiency of illumination is defined as the

Rank the following salts in order of decreasing pH of their 0.1 M aqueous solutions.(a) FeCl2, FeCl3, MgCl2, KClO2 .(b) NH4Br, N

Firlakuza [10]

Answer:

a) FeCl2, FeCl3, MgCl2, KClO2.

KClO2 --> K+ + ClO2-; ClO2- will hydrolyse to form HClO +OH-

Mg+2, Fe+2 and Fe+3 ions will form acidic solutions, since theyfom slightly amount of

Mg+2 + 2H2O <-> Mg(OH)2 + 2H+

Fe+2 + 2H2O <-> Fe(OH)2 + 2H+

Fe+3 + 3H2O <-> Fe(OH)3 + 3H+

Therefore;

decreasing pH is high pH to low pH:

KClO2 > MgCl2 > FeCl2 > FeCl3

b) NH4Br, NaBrO2, NaBr, NaClO2.

NH4Br is acidic, forms NH4+ and NH4+ dnates H+ to form NH3 andH+

NaBrO2 is basic, forms Na+ + BrO2- then H2O + BrO2- HBrO2

NABr is neutral, NaClO2 is basics, forms Na+ + ClO2-then H2O + ClO2- HClO2

decreasig pH:

NaClO2 > NaBrO2 > NaBr >NH4Br

Note that HClO2 is stronger acid than HBrO2, therefore, expectmore HBrO2 formation

NaBrO2 > NaClO2 > NaBr >NH4Br

5 0

3 years ago

2C3H7OH + 9O2 --> 6CO2 + 8H2O

Ne4ueva [31]

<h3>Answer:</h3>

733 g CO₂

<h3>General Formulas and Concepts:</h3>

<u>Math</u>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right<u> </u>

<u>Chemistry</u>

<u>Atomic Structure</u>

Reading a Periodic Table

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[RxN - Balanced] 2C₃H₇OH + 9O₂ → 6CO₂ + 8H₂O

[Given] 5.55 mol C₃H₇OH

<u>Step 2: Identify Conversions</u>

[RxN] 2 mol C₃H₇OH → 6 CO₂

Molar Mass of C - 12.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of CO₂ - 12.01 + 2(16.00) = 44.01 g/mol

<u>Step 3: Stoichiometry</u>

Set up conversion: $\displaystyle 5.55 \ mol \ C_3H_7OH(\frac{6 \ mol \ CO_2}{2 \ mol \ C_3H_7OH})(\frac{44.01 \ g \ CO_2}{1 \ mol \ CO_2})$
Multiply/Divide: $\displaystyle 732.767 \ g \ CO_2$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 3 sig figs.</em>

732.767 g CO₂ ≈ 733 g CO₂

8 0

3 years ago

An atom of a particular element is traveling at 1.00% of the speed of light. The de Broglie wavelength is found to be 3.31 × 10-

ExtremeBDS [4]

Answer:

The given atom is of Ca.

Explanation:

Given data:

Speed of atom = 1% of speed of light

De-broglie wavelength = 3.31×10⁻³ pm (3.31×10⁻³ / 10¹² = 3.31×10⁻¹⁵ m)

What is element = ?

Solution:

Formula:

m = h/λv

m = mass of particle

h = planks constant

v = speed of particle

λ = wavelength

Now we will put the values in formula.

m = h/λv

m = 6.63×10⁻³⁴kg. m².s⁻¹/3.31×10⁻¹⁵ m ×( 1/100)×3×10⁸ m/s

m = 6.63×10⁻³⁴kg. m².s⁻¹/ 0.099×10⁻⁷m²/s

m = 66.97×10⁻²⁷ Kg/atom

or

6.69×10⁻²⁶ Kg/atom

Now here we will use the Avogadro number.

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

Now in given problem,

6.69×10⁻²⁶ Kg/atom × 6.022 × 10²³ atoms/ mol × 1000 g/ 1kg

40.3×10⁻³×10³g/mol

40.3 g/mol

So the given atom is of Ca.

8 0

3 years ago

5. Which of the following is NOT a colligative property of a solution? (1 point) boiling point elevation supersaturation vapor p

LUCKY_DIMON [66]

142 ml
that is the anwser

3 0

3 years ago

The temperature and number of moles of a gas are held constant. Which of the following is true for the pressure of the gas?

Taya2010 [7]

Answer:

Pressure is inversely proportional to the volume of gas.

Explanation:

According to Boyle's law,

The volume of given amount of gas is inversely proportional to the pressure applied on gas at constant volume and number of moles of gas.

Mathematical expression:

P ∝ 1/ V

P = K/V

PV = K

when volume is changed from V1 to V2 and pressure from P1 to P2 then expression will be.

P1V1 = K P2V2 = K

P1V1 = P2V2

3 0

4 years ago