Alkanes are hydrocarbons that contain ____

Half of the first 18 elements have an odd number of electrons, and half have an even number. Show why atoms of these elements ar

asambeis [7]

Answer:

Diamagnetism in atom occurs whenever two electrons in an orbital paired equalises with a total spin of 0.

Paramagnetism in atom occurs whenever at least one orbital of an atom has a net spin of electron. That is a paramagnetic electron is just an unpaired electron in the atom.

Here is a twist even if an atom have ten diamagnetic electrons, the presence of at least one paramagnetic electron, makes it to be considered as a paramagnetic atom.

Simply put paramagnetic elements are one that have unpaired electrons, whereas diamagnetic elements do have paired electron.

The atomic orbital and radius increases by gaining electron linearly so even electron numbered atoms are diamagnetic while the odd electron numbered atoms are paramagnetic.

Running through the first 18 elements one can observe that there is an alternative odd number of electrons and an even number proofing that that half of the first 18 elements shows paramagnetism and diamagnetism respectively.

Explanation:

3 0

3 years ago

How many significant figures does 0.0006510 of have?

arsen [322]

It has 4 significant figures. If you see the Zero after the one decimal point you don’t count that and instead just started at 6

7 0

3 years ago

Read 2 more answers

2. Calculate the joules of energy required to heat 454.3g of water frum 5.4°C to 98.6°C.

Tasya [4]

Answer:

176984.38J

Explanation:

E = mC∆T

Where E is the energy in joules

M is the mass of water

C is the specific heat capacity of water =4.184J/g°C

It is known that it will take 4.184J of energy to change the temperature of water by one degree Celsius.

∆T = 98.6°c - 5.4°c

= 93.2°c

∆H = 454.3g × 4.18J/g°C × 93.2°c

= 176984.3768

176984.38J

7 0

3 years ago

A 100.0 mL solution containing 0.923 gof maleic acid (MW=116.072 g/mol) is titrated with 0.265 M KOH. Calculate the pH of the so

Vlad1618 [11]

Answer:

pH = 9,57

[M²⁻] = 7,948x10⁻²M

[HM⁻] = 4x10⁻⁵M

[H₂M] = 0M

Explanation:

The moles of maleic acid presents in the solution are:

0,923g× $\frac{1mol}{116,072g}$ =7,952x10⁻³moles of H₂M

60,0mL of 0,265M KOH are:

0,0600L× $\frac{0,265mol}{1L}$ =0,0159 moles of KOH

The reactions of maleic acid (H₂M) and then with HM⁻ are:

H₂M + KOH → HM⁻ + H₂O + K⁺ (1)

HM⁻ + KOH → M²⁻ + H₂O + K⁺ (2)

For a complete transformation of H₂M in HM⁻ there are necessaries 7,952x10⁻³moles of KOH. As the moles of KOH are 0,0159 moles, the restant moles are:

0,0159 - 7,952x10⁻³ = 7,948x10⁻³ moles of KOH

By (2), the moles produced of M²⁻ are the same as moles of KOH, 7,948x10⁻³ moles, and moles of HM⁻ are:

7,952x10⁻³ - 7,948x10⁻³ = 4x10⁻⁶ moles of HM⁻

Using Henderson-Hasselbalch formula:

pH = pka + log₁₀ [M²⁻] /[HM⁻]

pH = 6,27 + log₁₀ 7,948x10⁻³ / 4x10⁻⁶

pH = 9,57

The moles of M²⁻ are 7,948x10⁻³ and volume of the solution is 0,1000L,

[M²⁻] = 7,948x10⁻²M

Moles of HM⁻ are 4x10⁻⁶:

[HM⁻] = 4x10⁻⁵M

And there is not H₂M:

[H₂M] = 0M

I hope it helps!

8 0

3 years ago

How many grams of lead sulfide from when 10.0 g of lead are heated with 3.0 g of sulfur

zaharov [31]

The reaction forms 11.5 g PbS.

We have the masses of two reactants, so this is a limiting reactant problem.

We know that we will need a balanced equation with masses, moles, and molar masses of the compounds involved.

Step 1. Gather all the information in one place with molar masses above the formulas and everything else below them.

M_r: 207.2 32.06 239.28

Pb + S → PbS

Mass/g: 10.0 3.0

Step 2. Calculate the moles of each reactant

Moles of Pb = 10.0 g Pb × (1 mol Pb /207.2 g Pb) = 0.048 26 mol Pb

Moles of S = 30 g S × (1 mol S/32.06 g S) = 0.9357 mol S

Step 3. Identify the limiting reactant

Calculate the moles of PbS we can obtain from each reactant.

From Pb: Moles of PbS = 0.048 26 mol Pb × (1 mol PbS/1 mol Pb )

= 0.048 26 mol PbS

From S: Moles of S = 0.9357 mol S × (1 mol PbS/1 mol S) = 0.9357 mol PbS

Pb is the limiting reactant because it gives the smaller amount of PbS.

Step 4. Calculate the mass of PbS.

Mass = 0.048 26 mol PbS × (239.28 g PbS/1 mol PbS) = 11.5 g PbS

The reaction produces 11.5 g PbS.

4 0

3 years ago

Alkanes are hydrocarbons that contain _____.