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2 years ago

Answer all 3 parts correctly and I will give you a Brainliest, 5-star rating, and thanks on question and profile

Chemistry

2 answers:

Nat2105 [25]2 years ago

6 0

Answer:

different types of waves are due to how and where they are formed

Explanation:

Don't give me brainliest I only know first part.

pishuonlain [190]2 years ago

4 0

Answer:

Mark me as brain list plz for fun

Explanation:

The picture is blurry

You might be interested in

1) If calcium were to combine with the compound barium nitrate, which member of the barium nitrate would calcium replace?

snow_tiger [21]

Answer:

Calcium would displace barium.

Explanation:

Ba(NO₃)₂ + Ca --> Ca(NO₃)₂ + Ba

There are two types of compounds: molecular/covalent and ionic.

Molecular/covalent compounds are non-metal + non-metal.

Ionic compounds are metal + non-metal.

Looking at the periodic table, barium is a metal. Calcium is also a metal.

Checking a polyatomic ions chart would tell you NO₃⁻ is a non-metal because it has a negative charge.

Since there is no metal + metal compound, the calcium metal would displace barium. The compound remains ionic.

7 0

2 years ago

State Hund's rule.

loris [4]

Answer:

C. The lowest-energy electron configuration of an atom has the maximum number of unpaired electrons, all of which have the same spin, in degenerate orbitals.

Explanation:

The Hund's rule is used to place the electrons in the orbitals is it states that:

1. Every orbital in a sublevel is singly occupied before any orbital is doubly occupied;

2. All of the electrons in singly occupied orbitals have the same spin.

So, the electrons first seek to fill the orbitals with the same energy (degenerate orbitals) before paring with electrons in a half-filled orbital. Orbitals doubly occupied have greater energy, so the lowest-energy electron configuration of an atom has the maximum number of unpaired electrons, and for the second statement, they have the same spin.

The other alternatives are correct, but they're not observed by the Hund's rule.

6 0

3 years ago

If you place 1.0 L of ethanol (C2H5OH) in a small laboratory that is 3.0 m long, 2.0 m wide, and 2.0 m high, will all the alcoho

ankoles [38]

If you place 1.0 L of ethanol (C2H5OH) in a small laboratory that is 3.0 m long, 2.0 m wide, and 2.0 m high, will all the alcohol evaporate? If some liquid remains, how much will there be? The vapor pressure of ethyl alcohol at 25 °C is 59 mm Hg, and the density of the liquid at this temperature is 0.785g/cm^3 .

will all the alcohol evaporate? or none at all?

Answer:

Yes, all the ethanol present in the laboratory will evaporate since the mole of ethanol present in vapor is greater. The volume of ethanol left will therefore be zero.

Explanation:

Given that:

The volume of alcohol which is placed in a small laboratory = 1.0 L

Vapor pressure of ethyl alcohol at 25 ° C = 59 mmHg

Converting 59 mmHg to atm ; since 1 atm = 760 mmHg;

Then, we have:

= $\frac{59}{760}atm$

= 0.078 atm

Temperature = 25 ° C

= ( 25 + 273 K)

= 298 K.

Density of the ethanol = 0.785 g/cm³

The volume of laboratory = l × b × h

= 3.0 m × 2.0 m × 2.5 m

= 15 m³

Converting the volume of laboratory to liter;

since 1 m³ = 100 L; Then, we have:

15 × 1000 = 15,000 L

Using ideal gas equation to determine the moles of ethanol in vapor phase; we have:

PV = nRT

Making n the subject of the formula; we have:

$n = \frac{PV}{RT}$

$n = \frac{0.078 * 15000}{0.082*290}$

n = 47. 88 mol of ethanol

Moles of ethanol in 1.0 L bottle can be calculated as follows:

Since numbers of moles = $\frac{mass}{molar mass}$

and mass = density × vollume

Then; we can say ;

number of moles = $\frac{density*volume }{molar mass of ethanol}$

number of moles = $\frac{0.785g/cm^3*1000cm^3}{46.07g/mol}$

number of moles = $\frac{&85}{46.07}$

number of moles = 17.039 mol

Thus , all the ethanol present in the laboratory will evaporate since the mole of ethanol present in vapor is greater. The volume of ethanol left will therefore be zero.

5 0

2 years ago

Is temperature beginning to rise a physical or chemical change?

Lelu [443]

Answer:

If temperature increases, as it does in most reactions, a chemical change is likely to be occurring. This is different from the physical temperature change. During a physical temperature change, one substance, such as water is being heated.

Explanation:

6 0

2 years ago

Read 2 more answers

Question 3 (1 point)

pentagon [3]

Full question:

The IUPAC name for CH3CH2C≡CCH3 is:

Answer:

2-pentyne

Explanation:

To name hydrocarbons, you first you have to identify the longest carbon chain. There are 5 carbons in this chain, so we know the name is "pent".

You then have to identify the presence of any double or triple bonds. If double bonds, it is an alkene, if triple bonds, it is an alkyne. In this case there is a triple bond, so we know the hydrocarbon is pentyne.

You then number the chain to give the lowest number to the triple bond. It could either be 4 (countnig carbons from left to right) or 2 (from right to left). Therefore, the answer is 2-pentyne.

5 0

3 years ago