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3 years ago

TVINN

Chemistry

1 answer:

liq [111]3 years ago

3 0

Answer:

Assertion (A) is true

but reason (R) is false.

Explanation:

If we look at the assertion closely, it is true that a sublime substance changes from solid to gas without passing through a liquid state. Naphthalene, camphor, iodine and ammonium chloride are some common examples of the substances which undergo sublimation.

However, not all solids first pass through a liquid state before converting to gas. Sublime solids such as those listed above passes directly from solid to gas without passing through a liquid state.

Hence the assertion is true but reason is false.

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Which property of matter changes during a chemical change but not during a physical change

andrew-mc [135]

Answer:In a physical change, atoms are not rearranged and the matter's physical and chemical properties are unchanged. Chemical changes, on the other hand, rearrange the atoms of matter in new combinations, resulting in matter with new physical and chemical properties.

Explanation:

easy

8 0

4 years ago

What is the equation for the acid dissociation constant, Ka, of HF?

VashaNatasha [74]

Answer:

hydrofluoric acid HF H+ + F- 7.2 × 10-4

4 0

3 years ago

Draw a structure for the product of nucleophilic substitution obtained on solvolysis of tert−butyl bromide in methanol

DENIUS [597]

Answer:

methyl tert-butyl ether is produced as a product

Explanation:

Nucleophilic substitution in solvolysis reaction of tert-butyl bromide goes through $S_{N}1$ mechanism.
Because Br is a good leaving group due to it's large size and high polarizability and methanol is an weak nucleophile.
In the first step, tert-butyl cation is produced. In the second step, methanol attacks the carbocation and produce methyl tert-butyl ether after deprotonation.
Reaction and structure of product has been shown below.

4 0

3 years ago

Explain why NO is more soluble in water than either N2 or O2. Fill in the following blanks.

jek_recluse [69]

Answer:

a. Larger molecular size

b. Ability to react with water

c. Polarity

d. Shorter bond length

Explanation:

Ethene is a larger molecule than oxygen and nitrogen hence it is more soluble than the both other gases .

SO2 dissolves readily in water to yield an acid solution. It is an acid anhydride.

Nitric oxide is a polar compound. It remains very much polar while nitrogen and oxygen are non polar.

Nitrogen is sp hybrized, this leads to a very short bond and does not easily interact with oxygen and nitrogen

3 0

3 years ago

An aqueous solution of hydrobromic acid is standardized by titration with a 0.164 M solution of calcium hydroxide. If 14.9 mL of

Arada [10]

Answer:

The molarity of hydrobromic acid is 0.182 M

Explanation:

Step 1: Data given

Molarity of Calcium hydroxide = 0.164 M

Volume of calcium hydroxide = 14.9 mL = 0.0149 L

Volume of HBr = 26.9 mL = 0.0269 L

Step 2: The balanced equation

Ca(OH)2 + 2HBr →CaBr2 + 2H2O

Step 3: Calculate molarity of HBr

b*Ca*Va = a*Cb*Vb

⇒b = the coefficient of HBr = 2

⇒Ca = the molarity of Ca(OH)2 = 0.164 M

⇒Va = the volume of ca(OH)2 = 0.0149 L

⇒a= the coefficient of Ca(OH)2 = 1

⇒Cb = the molarity of HBr = TO BE DETERMINED

⇒Vb = the volume of HBr = 0.0269 L

2*0.164 * 0.0149 = 1*Cb*0.0269

Cb = 0.182 M

The molarity of hydrobromic acid is 0.182 M

6 0

4 years ago