Odor extensive or intensive

What allows scientists to find the actual age of some object (or some event)

dangina [55]

They can use carbon dating or lithium argon dating.

5 0

4 years ago

In the laboratory a student determines the specific heat of a metal. She heats 19.6 grams of zinc to 98.37°C and then drops it i

fgiga [73]

Answer:

The specific heat of zinc is 0.375 J/g°C

Explanation:

Step 1: Data given

Mass of zinc = 19.6 grams

Mass of water = 82.9 grams

Initial temperature of zinc = 98.37 °C

Initial temperature of water = 24.16 °C

Final temperature of water (and zinc) = 25.70 °C

Specific heat of water = 4.184 J/g°C

Step 2: Calculate Specific heat of zinc

Heat lost by zinc = heat won by water

Q=m*c*ΔT

Qzinc = -Qwater

m(zinc)*C(zinc)*ΔT(zinc) = -m(water)*C(water)*ΔT(water)

⇒ with mass of zinc = 19.6 grams

⇒ with C(zinc) = TO BE DETERMINED

⇒ with ΔT(zinc) = T2 -T1 = 25.70 - 98.37 = -72.67°C

⇒ with mass of water = 82.9 grams

⇒ with C(water) = 4.184 J/g°C

⇒ with ΔT(water) = T2 - T1 = 25.70 - 24.16 = 1.54

Qzinc = -Qwater

19.6g* C(zinc) * (-72.67°C) = - 82.9g* 4.184 J/g°C * 1.54 °C

-1424.332*C(zinc) = -534.155

C(zinc) = 0.375 J/g°C

The specific heat of zinc is 0.375 J/g°C

7 0

3 years ago

Q3. Which of the following objects are chiral and which are achiral? a

Sergio039 [100]

Answer:

See explanation

Explanation:

In this question, we have to follow the IUPAC rules. Lets analyze each compound:

a. 1-methylbutane

In this compound we have a chain of 5 carbons, so the correct name is Pentane.

b. 1,1,3-trimethylhexane

In this compound, we longest chain is made of 7 carbons, so, we have to use the name "heptane". Carbon one would be the closet one to the methyl group, so the correct name is 2,4-dimethylheptane.

c. 5-octyne

In this case, carbon 1 would be the closet one to the triplet bond. With this in mind, the correct name is oct-3-yne.

d. 2-ethyl-1-propanol

In this compound, we longest chain is made of 4 carbons, so, we have to use the name "butane". Carbon one would be the carbon with the "OH" group, so the correct name is 2-methylbutan-1-ol.

e. 2.2-dimethyl-3-butanol

In this case, carbon 1 would be the closet one to the "OH". With this in mind, the correct name is 3,3-dimethylbutan-2-ol.

See figure 1

I hope it helps!

3 0

4 years ago

How many grams of a 23.4% by mass naf solution is needed if you want to have 1.33 moles of naf?

jenyasd209 [6]

Percentage by mass is the mass of NaF present in 100 g of the solution.
the percentage by mass of NaF is 23.4 %
this means that in 100 g of solution, mass of NaF present is 23.4 g
the number of moles of NaF present - 1.33 mol
mass of NaF - 1.33 mol x 42 g/mol = 55.9 g
when there's 23.4 g of NaF - mass of solution is 100 g
therefore when there's 55.9 g of NaF - mass of solution is 100 / 23.4 x 55.9
= 239 g
mass of solution required is 239 g

6 0

4 years ago

The IUPAC rules permit the use of common names for a number of familiar phenols and aryl ethers. These common names are listed h

fgiga [73]

Explanation:

a. Vanillin(4-hydroxy-3-methoxybenzaldehyde):

In its structure hydroxl group will be present on para position of the benzaldehyde ring and methoxy group on meta position.

b. Thymol (2-isopropyl-5-methylphenol):

In its structure isopropyl group will be present on ortho position of the phenol ring and methyl group on meta position.

c. Carvacrol (5-isopropyl-2-methylphenol):

In its structure isopropyl group will be present opposite to methyl group which is present ortho position in a phenol ring.

d. Eugenol (4-allyl-2-methoxyphenol):.

In its structure allyl group will be present on para position of the phenol ring and methoxy group on ortho position.

e. Gallic acid (3,4,5-trihydroxybenzoic acid):

In its structure hydroxyl group will be present on both meta positions and on para position of the benzoic acid ring.

f. Salicyl alcohol (o-hydroxybenzyl alcohol):

In its structure, $-CH_2OH$ group is linkedto benzene ring and in respect to that hydroxyl group is present at ortho position of the ring.

6 0

3 years ago