Which of the following is the best way to

malfutka [58]

Answer: $6.48*10^{-2}$

Explanation:

alright, dawg, lets get this bread. CHEMISTRY? OH YEAH I LOVE CHEMISTRY.

what is a mol? do you know who avogadro is? sounds like avocado. free shavocado. ok so you MUST REMEMBER THIS NUMBER PLEASE.

please remember this number and commit it to your memory: avogadros number

$6.02 * 10^{23}$

this is how much a mole is. you know how a pair is 2 and a dozen is 12? ok so a mole is $6.02 * 10^{23}$ it is confusing at first but hopefully this helps you to understand.

now that we understand this..... lets perform this calculation with a calculator

$(3.90 * 10^{22}) / (6.02 * 10^{23})$

notice i divide the question by the avogadros number to find out how many moles are in the number. ok but listen... it gets into a tough area here... because HOW ARE WE TO DIVIDE SUCH A HUMONGOUS NUMBER BY ANOTHER HUMONGOUS NUMBER?!?!?

its easy, its cake, just listen this is how you do it. only focus on the numbers NOT the 10 exponential ones. so just 3.90 and 6.02 ok? lets divide these two numbers 3.90 / 6.02 and we get 0.6478... how interesting... ok now lets deal with the exponents of 10. notice that we are DIVIDING these numbers so think of it as subtracting the exponents of ten..... 22 minus 23 equals -1

so we have $0.6478 * 10^{-1}$

now this negative 1 thing is annoying so lets just make it to the power of 0

$0.06478 * 10^{0}$

and anything to the power of 0 just becomes 1.

0.06478

so this is our answer but keep in mind we need 3 sig figs. if we round then we get 0.0648

put this into scientific notation we get $6.48*10^{-2}$

5 0

3 years ago

Given that hclo4 is a strong acid, how would you classify the basicity of clo−4?

Mandarinka [93]

As a conjugate base of a strong acid,ClO4-would be classified as having a negligible basicity. The basicity of a chemical species is normally expressed by the acidity of the conjugate acid. The basicity of an acid is the number of hydrogen ions, which can be produced by one molecule of the acid.

8 0

3 years ago

How can i find the number of neutrons in an element

lawyer [7]

Answer:

The mass number is the sum of protons and neutrons. This means to find the number of neutrons you subtract the number of protons from the mass number. On the periodic table, the atomic number is the number of protons, and the atomic mass is the mass number.

Explanation:

7 0

3 years ago

Read 2 more answers

Balance the chemical equation _CrO3->_Cr2O3+_O2

snow_lady [41]

Answer:

2CrO3-->2Cr2O3--->3O2

7 0

2 years ago

You have 26.7 mL of 0.061 mol/L aqueous potassium hydroxide (KOH(aq)) in a conical flask. In a burette

Natasha2012 [34]

Answer:

9.47 mL

Explanation:

The reaction that takes place is:

2KOH + H₂SO₄ → K₂SO₄ + 2H₂O

First we calculate how many KOH moles reacted, using the given concentration and volume of KOH solution:

0.061 mol/L = 0.061 mmol/mL

0.061 mmol/mL * 26.7 mL = 1.6287 mmol KOH

Then we convert KOH moles into H₂SO₄ moles, using the stoichiometric coefficients:

1.6287 mmol KOH * $\frac{1mmolH_2SO_4}{2mmolKOH}$ = 0.8144 mmol H₂SO₄

Finally we calculate the required volume of the H₂SO₄ solution, using the number of moles and given concentration:

0.8144 mmol ÷ 0.086 mmol/mL = 9.47 mL

5 0

3 years ago