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2 years ago

If the radius of a coin is 14 cm, What is surface area?

1 answer:

5 0

Let R=radius

Surface area of coin = π r²
where π can be typed in scientific calculator

Answer: π x 14 x 14 = 615.752 cm²

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13. List the following ions in order of increasing radius: Li+, Mg2+, Br"

Sergeeva-Olga [200]

Answer:

The answer would be B, PC13

Explanation:

5 0

1 year ago

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What term describes a carbon atom that has four different groups bonded to it?

oee [108]

A carbon which is attached to four different atoms or group of atoms with different environment is called as Chiral Carbon or Asymmetric Carbon.

Non-superimposable:
 The mirror image (molecule) of chiral carbon cotaining compounds are Non.Superimposable on each other. They are called enantiomers of each other.

Polarized Light and Chiral Carbon:
When a polarized light is allowed to fall on either enantiomer of chiral compound, it is rotated other clockwise or anti-clockwise.

Examples:
Below are three axamples of compounds containing chiral carbon.

8 0

2 years ago

Sodium sulfate is slowly added to a solution containing 0.0500 M Ca 2 + ( aq ) and 0.0390 M Ag + ( aq ) . What will be the conce

levacccp [35]

The given question is incomplete. The complete question is as follows.

Sodium sulfate is slowly added to a solution containing 0.0500 M $Ca^{2+}(aq)$ and 0.0390 M $Ag^{+}(aq)$ . What will be the concentration of $Ca^{2+}$ (aq) when $Ag_{2}SO_{4}(s)$ begins to precipitate? What percentage of the $Ca^{2+}(aq)$ can be separated from the Ag(aq) by selective precipitation?

Explanation:

The given reaction is as follows.

$Ag_{2}SO_{4} \rightleftharpoons 2Ag^{+} + SO^{2-}_{4}$

$[Ag^{+}]$ = 0.0390 M

When $Ag_{2}SO_{4}$ precipitates then expression for $K_{sp}$ will be as follows.

$K_{sp} = [Ag^{+}]^{2}[SO^{2-}_{4}]$

$1.20 \times 10^{-5} = (0.0390)^{2} \times [SO^{2-}_{4}]$

$[SO^{2-}_{4}]$ = 0.00788 M

Now, equation for dissociation of calcium sulfate is as follows.

$CaSO_{4} \rightleftharpoons Ca^{2+} + SO^{2-}_{4}$

$K_{sp} = [Ca^{2+}][SO^{2-}_{4}]$

$4.93 \times 10^{-5} = [Ca^{2+}] \times 0.00788$

$[Ca^{2+}]$ = 0.00625 M

Now, we will calculate the percentage of $Ca^{2+}$ remaining in the solution as follows.

$\frac{0.00625}{0.05} \times 100$

= 12.5%

And, the percentage of $Ca^{2+}$ that can be separated is as follows.

100 - 12.5

= 87.5%

Thus, we can conclude that 87.5% will be the concentration of $Ca^{2+}(aq)$ when $Ag_{2}SO_{4}(s)$ begins to precipitate.

4 0

2 years ago

If 10.0 mL of a .600 M of HNO3 reacts with 31.0 mL of .700M Ba(OH)2 solution, what is the molarity of Ba(OH)2 after the reaction

Tasya [4]

Answer:

0.456M

Explanation:

1. Balanced molecular equation

$2HNO_3+Ba(OH)_2\rightarrow Ba(NO_3)_2+2H_2O$

2. Mole ratio

$\dfrac{2molHNO_3}{1molBa(OH)_2}$

3. Moles of HNO₃

Number of moles = Molarity × Volume in liters
n = 0.600M × 0.0100 liter = 0.00600 mol HNO₃

4. Moles Ba(OH)₂

n = 0.700M × 0.0310 liter = 0.0217 mol

5. Limiting reactant

Actual ratio:

$\dfrac{0.0600molHNO_3}{0.0217molBa(OH)_2}\approx0.28$

Since the ratio of the moles of HNO₃ available to the moles of Ba(OH)₂ available is less than the theoretical mole ratio, HNO₃ is the limiting reactant.

Thus, 0.006 moles of HNO₃ will react completely with 0.003 moles of Ba(OH)₂ and 0.0217 - 0.003 = 0.0187 moles will be left over.

6. Final molarity of Ba(OH)₂

Molarity = number of moles / volume in liters
Molarity = 0.0187 mol / (0.0100 + 0.0031) liter = 0.456M

5 0

2 years ago

As the temperature of a gas increases, which of the following explains the effect on the average kinetic energy of the gas?

lidiya [134]

As the temperature of a gas increases, the kinetic energy of the gas particles will also increase. As the temperature of the gas increase, the gas particles gains more energy to move faster, they thus collide more with one another and with the wall of the container, thus increasing pressure as well. So, as the temperature of a gas increases, the kinetic energy increases and the pressure increases as well if the gas is inside an inflexible container.

8 0

2 years ago

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