Which are homogeneous mixtures? check all that apply

Predict the empirical formula of the ionic compound that forms from aluminum and oxygen.

sertanlavr [38]

Answer:

A. AlO

Explanation:

The empirical formula of a compound is the simplest possible formula giving the ratio of atoms in a molecule of the compound.

We know that Aluminium forms $Al^{3+}$ and oxygen forms $O^{2+}$ .

As such the formation of the ionic compound between a metal and non-metal results into $Al_2O_3$ .

The empirical formula is as follows:

Element Aluminium Oxygen

% composition

by mass 26.98 16.0

mole ratio 26.98/26 16/16

= 1.04 = 1

divided by the

smallest number 1.04/1 1/1

1.04 1

The empirical formula is AlO

8 0

4 years ago

The 1H NMR spectrum of chloroethane (CH3CH2Cl) recorded on a 500 MHz NMR spectrometer consists of signals at chemical shifts of

sleet_krkn [62]

Answer:The frequency of absorption for the proton having chemical shift 1.48 ppm is 740 Hz downfield from TMS.

The frequency of absorption for the proton having chemical shift 3.57 ppm is 1785 Hz downfield from TMS.

Explanation:

We are given with the following data:

Frequency of the instrument(NMR spectrometer)=500MHz=500×10⁶Hz

Chemical shift (δ) value for 1st proton=1.48PPM=1.48×10⁻⁶

Chemical shift (δ) value for 2nd proton=3.57PPM=3.57×10⁻⁶

We know that frequency of reference that is of TMS(Tetramethylsilane) is assumed to be 0.

We have to calculate the frequency of absorption of each protons downfield from TMS.

The formula for the chemical shift (δ) is:

δ=[Frequency of sample(νₐ)-Frequency of TMS(νₓ)]÷Frequency of instrument MHz(Mega Hertz)

So using the above formula we can calculate the frequency of absorption for the two protons whose δ value is given.

1. For the proton having δ value 1.48ppm:

1.48= [Frequency of sample(νₐ)-Frequency of TMS(νₓ)]÷Frequency of instrument MHz(Mega Hertz)

1.48×10⁻⁶=[Frequency of sample(νₐ)-0]÷[500×10⁶Hz]

1.48×10⁻⁶×500×10⁶Hz=[Frequency of sample(νₐ)]

740Hz=[Frequency of sample(νₐ)]

2. For the proton having δ value 3.57ppm:

3.57= [Frequency of sample(νₐ)-Frequency of TMS(νₓ)]÷Frequency of instrument MHz(Mega Hertz)

3.57×10⁻⁶=[Frequency of sample(νₐ)-0]÷[500×10⁶Hz]

3.57×10⁻⁶×500×10⁶Hz=[Frequency of sample(νₐ)]

1785Hz=[Frequency of sample(νₐ)]

So the frequency of absorption for the proton having δ value 1.48ppm is 740 Hz and for the proton having δ value 3.57 ppm is 1785Hz.

3 0

3 years ago

For chemical reactions involving ideal gases, the equilibrium constant K can be expressed either in terms of the concentrations

miskamm [114]

Answer:

$K_p= 3966.01$

Explanation:

The relation between Kp and Kc is given below:

$K_p= K_c\times (RT)^{\Delta n}$

Where,

Kp is the pressure equilibrium constant

Kc is the molar equilibrium constant

R is gas constant

T is the temperature in Kelvins

Δn = (No. of moles of gaseous products)-(No. of moles of gaseous reactants)

For the first equilibrium reaction:

$2CH_4_{(g)}\rightleftharpoons C_2H_2_{(g)}+3H_2_{(g)}$

Given: Kc = 0.140

Temperature = 1778 °C

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T = (1778 + 273.15) K = 2051.15 K

R = 0.082057 L atm.mol⁻¹K⁻¹

Δn = (3+1)-(2) = 2

Thus, Kp is:

$K_p= 0.140\times (0.082057\times 2051.15)^{2}$

$K_p= 3966.01$

6 0

3 years ago

Anna’s mother prepares sauerkraut, a fermented dish made from finely cut cabbage and salt. Lactobacillus bacteria present on the

kari74 [83]

The answer is D. Lactic Acid Fermentation!

6 0

3 years ago

Read 2 more answers

Calcium oxide is used to remove the pollutant SO2 from smokestack gases. The overall reaction is:

fgiga [73]

This problem is providing a chemical reaction reaction at equilibrium and its pressure-based equilibrium constant, and thus asks for molecules of SO2 at equilibrium. At the end, the answer turns out to be 1.25x10¹² molecules.

<h3>Chemical equilibrium</h3>

In chemistry, when chemical reactions take place, they do not necessarily go to completion, but can reach a constant-concentration point denominated "equilibrium" where the reaction does not proceed any longer.

In such a way, for the given reaction, one can write the equilibrium expression based on the law of mass action, which sets the products on top, reactants on bottom and ignores both solids and liquids:

$Kp=\frac{1}{p_{SO_2}*p_{O_2}^{1/2}}$

However, in order to calculate this, one needs the partial pressure of O2, defined in similar problems as 0.21 atm for us to find the partial pressure of SO2 first:

$2.38x10^{15}=\frac{1}{p_{SO_2}*(0.21)^{1/2}}\\\\p_{SO_2}=\frac{1}{(2.38x10^{15})(0.21)^{1/2}}\\\\p_{SO_2}=9.17x10^{-16}atm$

Keep in mind this 0.21 atm may vary depending on the problem you were given.

Thus, we obtain the mole fraction of SO2 as follows:

$x_{SO_2}=\frac{9.17x10^{-16}atm}{9.17x10^{-16}atm+0.21atm}=4.37x10^{-15}\\ \\$

Finally, we use this mole fraction to calculate the moles of SO2 in 475 moles of the gas mixture, and then use the Avogadro's number to calculate the molecules:

$molecules=475mol*4.37x10^{-15}*\frac{6.022x10^{23}}{1mol} =1.25x10^{12}molecules$

Learn more about chemical equilibrium: brainly.com/question/26453983

6 0

3 years ago