Which sample at STP has the same number of molecules as 5 liters of NO2(g) at STP?

Answer the following questions based on the reaction below: NaOH(aq) + KHP(s) --> NaKP(aq)+H2O(I)

Natali [406]

Answer:

a) 1.44g

b) 77.3%

Explanation:

1. Chemical balanced equation (given)

$NaOH(aq)+ KHP(s)\rightarrow NaKP(aq)+H_2O(l)$

2. Mole ratio

$1molNaOH(aq):1molKHP(s)$

This is, 1 mol of NaOH will reacts with 1 mol of KHP.

3. Find the number of moles in 72.14 mL of the base

$Molarity=\text{number of moles of solute}/\text{volume of solution in liters}$

$\text{Volume of solution}=72.14mL=0.07214liters$

$\text{Number of moles of NaOH}=0.0978M\times 0.07214liter=0.007055mol$

4. Find the number of grams of KHP that reacted

The number of moles of KHP that reacted is equal to the number of moles of NaOH, 0.007055 mol

Convert moles to grams:

mass = number moles × molar mass = 0.007055mol × 204.23g/mol

mass = 1.4408 g.

You have to round to 3 significant figures: 1.44 g (because the molarity is given with 3 significant figures).

5. Find the percentage of KHP in the sample

The percentage is how much of the substance is in 100 parts of the sample.

The formula is:

% = (mass of substance / mass of sample) × 100

% = (1.4408g/ 1.864g) × 100 = 77.3%

7 0

3 years ago

PLEASE PLEASE PLEASE HELP ME CHEM! DUE IN 10 MINS!! 20 POINTS (SPAM COMMENTS WILL BE BLOCKED) GIVING OUT BRAINLIEST

geniusboy [140]

Answer:

Natrium oxide

4 Na atoms

2 O atoms

Fluoride

6 F atoms

Lithium sulfate

8 Li atoms

16 SO atoms

Calcium

2 Ca atoms

Aluminum hydroxide

2 Al atoms

3 OH atoms

Manganese sulfate

2 Mn atoms

12 SO atoms

Cuprum chloride

1 Cu atom

2 CI atoms

8 0

3 years ago

Predict the products and then balance the equation

Aneli [31]

$\qquad \qquad\huge \underline{\boxed{\sf Answer}}$

Here's the balanced equation for given Double displacement reaction ~

$\sf Pb(NO_3)_2 +2 \: KI = PbI_2 +2 \: KNO_3$

The products fored are : Lead Iodide ( PbI2 ) and Potassium Nitrate ( KNO3 )

4 0

2 years ago

Read 2 more answers

A process at constant T and P can be described as spontaneous if ΔG < 0 and nonspontaneous if ΔG > 0. Over what range of t

creativ13 [48]

Answer:

Incomplete question, it is lacking the data it makes reference. The missing data from Chegg is:

2 SO3(g) → 2 SO2(g) + O2(g)

ΔHf° (kJ mol-1) -395.7 -296.8

S° (J K-1 mol-1) 256.8 248.2 205.1

ΔH° = kJ

S° = J K⁻¹

Explanation:

The method to solve this problem calls for the use of the Gibbs standard free energy change:

ΔG = ΔrxnH - TΔSrxn

We know a reaction is spontaneous when ΔG is < 0, so to answer this question we need to solve for the temperature, T, at which ΔG becomes negative.

Now as mentioned in the hint, we need to determine ΔrxnH and ΔSrxn, which are given by

ΔrxnH = ∑ ν x ΔfHº products - ∑ ν x ΔfHº reactants

where ν is the stoichiometric coefficient in the balanced chemical equation.

For ΔS we have likewise

ΔrxnS = ∑ ν x ΔSº products - ∑ ν x ΔSº reactants

Thus,

ΔrxnH(kJmol⁻¹) = 2 x (-296.8) - 2 x ( -395.7 ) = 197.8 kJ

ΔrxnS ( JK⁻¹) = 2 x 248.2 + 205.1 - 2 x 256.8 = 187.9 JK⁻¹ = 0.1879 kJK⁻¹

So ΔG kJ = 197.8 - T(0.1879)

and the reaction will become spontaneous when the term T(0.1879) becomes greater that 197.8,

0 = 197.8 - 0.1879 T ⇒ T = 1052 K

so the reaction is spontaneous at temperatures greater than 1052 K (780 ºC)

4 0

3 years ago

What is the difference between isotopes and allotrope not more than three line

Firdavs [7]

Answer:

An allotrope is one way that atoms can be arranged in a solid. An isotope is one way that protons and neutrons can form the same atomic element.

8 0

3 years ago

Read 2 more answers