Answer:
1.4 × 10² mL
Explanation:
There is some info missing. I looked at the question online.
<em>The air in a cylinder with a piston has a volume of 215 mL and a pressure of 625 mmHg. If the pressure inside the cylinder increases to 1.3 atm, what is the final volume, in milliliters, of the cylinder?</em>
Step 1: Given data
- Initial volume (V₁): 215 mL
- Initial pressure (P₁): 625 mmHg
- Final pressure (P₂): 1.3 atm
Step 2: Convert 625 mmHg to atm
We will use the conversion factor 1 atm = 760 mmHg.
625 mmHg × 1 atm/760 mmHg = 0.822 atm
Step 3: Calculate the final volume of the air
Assuming constant temperature and ideal behavior, we can calculate the final volume of the air using Boyle's law.
P₁ × V₁ = P₂ × V₂
V₂ = P₁ × V₁ / P₂
V₂ = 0.822 atm × 215 mL / 1.3 atm = 1.4 × 10² mL
The copper wire was sanded before burning in order to make sure that copper metal was exposed on the surface of the wire.
Answer: B
Explanation
The copper wire when placed in atmosphere without coating leads to oxidation of copper metal with respect to the impurities present in the atmosphere.
As copper is electropositive in nature, so electronegative ions present in the universe will try to react with copper and the copper will react easily with other elements.
So generally copper wire is coated with color or polymer coating.
In this case, the copper wire without any coating is sanded, so that the eddy sheets or polishing materials on friction with copper wire will remove the impurities by the electrostatic law of conservation of charges and charge transfer.
As the impurities are removed when copper wire is sanded, the copper atoms will be exposed on the surface of the wire leading to burning of copper in the copper wire.
Answer:
20 mL OF 6 M HYDROCHLORIC ACID WILL BE NEEDED
Explanation:
M1 V1 = M2 V2
M1 = Molarity of sodium hydroxide = 3 M
V1 = volume of sodium hydroxide = 40 mL
M2 = Molarity of hydrochloric acid = 6 M
V2 = Volume of hydrochloric acid = unknown
Rearranging the equation, we have:
V2 = M1 V1 / M2
V2 = 3 * 40 mL / 6
V2 = 120 / 6
V2 = 20 mL
To precipitate the benzoic acid by 6 M of hydrochloric acid, 20 mL volume will be needed.
Answer : The correct option is, (b) 22.1 g
Solution : Given,
Mass of iron = 15.5 g
Molar mass of iron = 56 g/mole
Molar mass of
= 160 g/mole
First we have to calculate the moles of iron.

Now we have to calculate the moles of
.
The balanced reaction is,

From the balanced reaction, we conclude that
As, 2 moles of iron obtained from 1 mole of 
So, 0.276 moles of iron obtained from
mole of 
Now we have to calculate the mass of 

Therefore, the amount of
required are, 22.1 grams.