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2 years ago

How many atoms are in 0.0246 mol K?

Chemistry

1 answer:

Alexxx [7]2 years ago

3 0

Answer:

There are 6.022 × 1023 atoms of potassium in every mole of potassium. Since one mole of KOH contains one mole of K, the answer is 6.022×1023 atoms of K.

Explanation:

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The number of ions in 17.1 gm of aluminum sulphate Al2 (SO4)3 =….. [Molar mass of Al2 (SO4)3 = 342 gm]

katen-ka-za [31]

Answer:

1.51 X 10^23 ions

Explanation:

The number of ions in 17.1 gm of aluminum sulphate Al2 (SO4)3 =….. [Molar mass of Al2 (SO4)3 = 342 gm]

in one molecule of Al2(SO4)3 there are 5 ions 2 aluminum and 3 sulfate ions

in 2 molecules there are 2X5= 10 ions

in 10 molecules there are 10X5 = 50 ions

molar mass of Al2(SO4)3 = (2 X 26.98) +( 3 X 32.1) + (3 X 4 X 16.0 ) =342.gms = 17.1/342 =0.0500 moles

1 mole =6.02 X 10^23 molecules ( see Avogadros number)

0.0500 moles = 0.0500 X 6.02 X 10^23 molecules =

0.301 X 10^23 molecules = 3.01 X 10^22 molecules

We determined that each molecule of Al2(SO4)3 has 5 ions

so 3.01 X10^22 molecules have 5 X 3.01 X 10^22 ions =

15.05 X 10^22 ions = 1.51 X 10^23 ions

3 0

2 years ago

What is an element that has more valence electrons than fluorine and less energy levels than sodium?

Radda [10]

From the periodic chart the only element between F and Na is Neon. Neon has one more valence electron 8 than fluorine 7, and is one energy level shy of Na.

5 0

2 years ago

he population of the Earth is roughly eight billion people. If all free electrons contained in this extension cord are evenly sp

wolverine [178]

1) Drift velocity: $3.32\cdot 10^{-4}m/s$

2) $5.6\cdot 10^{13}$ electrons per person

Explanation:

For a current flowing through a conductor, the drift velocity of the electrons is given by the equation:

$v_d=\frac{I}{neA}$

where

I is the current

n is the concentration of free electrons

$e=1.6\cdot 10^{-19}C$ is the electron charge

A is the cross-sectional area of the wire

The cross-sectional area can be written as

$A=\pi r^2$

where r is the radius of the wire. So the equation becomes

$v_d=\frac{I}{ne\pi r^2}$

In this problem, we have:

I = 8.0 A is the current

$8.5\cdot 10^{28} m^{-3}$ is the concentration of free electrons

d = 1.5 mm is the diameter, so the radius is

r = 1.5/2 = 0.75 mm = $0.75\cdot 10^{-3}m$

Therefore, the drift velocity is:

$v_d=\frac{8.0}{(8.5\cdot 10^{28})(1.6\cdot 10^{-19})\pi(0.75\cdot 10^{-3})^2}=3.32\cdot 10^{-4}m/s$

The total length of the cord in this problem is

L = 3.00 m

While the cross-sectional area is

$A=\pi r^2=\pi (0.75\cdot 10^{-3})^2=1.77\cdot 10^{-6} m^2$

Therefore, the volume of the cord is

$V=AL$ (1)

The number of electrons per unit volume is $n$ , so the total number of electrons in this cord is

$N=nV=nAL=(8.5\cdot 10^{28})(1.77\cdot 10^{-6})(3.0)=4.5\cdot 10^{23}$

In total, the Earth population consists of 8 billion people, which is

$N'=8\cdot 10^9$

Therefore, the number of electrons that each person would get is:

$N_e = \frac{N}{N'}=\frac{4.5\cdot 10^{23}}{8\cdot 10^9}=5.6\cdot 10^{13}$

7 0

3 years ago

Based on your knowledge of energy resources conservation, which of the following statements is true? a) Manufacturers can increa

Kruka [31]

Answer: Option (b) is the correct answer.

Explanation:

When useful energy is conserved then this conservation is known as energy conservation.

For example, when lights of a room are switched on where no one is sitting then on switching off the lights we are conserving wastage of electricity.

Thus, we can conclude that out of the given options, the statement energy resources can be conserved by turning off lights when they are not in use is true.

5 0

3 years ago

What is the most common two-drug combination that results in death?

VMariaS [17]

Prescription painkillers and alcohol
Mixing drugs is always dangerous, and some combinations interact in ways that are particularly deadly. The number of people who died from mixing opioids and alcohol increased more than 300% from 1999 to 2010.

7 0

3 years ago