Mixtures can be separated by filtration and distillation. Both methods take advantage of ...

In the reaction of aluminum hydroxide and caldium nitrate, how many grams of calcium hydroxide will be formed if 12.55 g of alum

Dahasolnce [82]

Answer:

17.76g

Explanation:

We need to write a balanced chemical equation for the reaction:

2Al(OH)3 + 3Ca(NO3)2 ——> 3Ca(OH)2 + 2Al(NO3)3

In the reaction above, it can be seen that 2 moles of aluminum hydroxide yielded 3 moles of calcium hydroxide. This is the theoretical viewpoint.

Now we need to know what actually happened. We need to calculate the actual number of moles of aluminum hydroxide reacted l. We can get this by dividing the mass by the molar mass.

The molar mass of aluminum hydroxide is 27+ 3( 16+1)

= 27 + 51 = 78g/mol

The number of moles is thus: 12.55/78 = 0.16 moles

Now if 2 moles of aluminum hydroxide gave 3 moles of calcium hydroxide, 0.16moles will give : (0.16*3)/2 = 0.24moles

Now we can calculate the mass of calcium hydroxide formed. The mass of calcium hydroxide formed is the number of moles multiplied by the molar mass.

The molar mass of calcium hydroxide is; 40 + 2(17) = 74g/mol

The mass is thus =74 * 0.24 = 17.76g

7 0

3 years ago

Based on the sign of E cell, classify these reactions as spontaneous or non spontaneous as written.? assume standard conditions.

sammy [17]

A electrochemical reaction is said to be spontaneous, if $E^{0} cell is positive.$

Answer 1:
Consider reaction: Ni^2+ (aq) + S^2- (aq) ----> + Ni (s) + S (s)

The cell representation of above reaction is given by;
 $S^{2-}/S // Ni^{2+}/Ni$

Hence, $E^{0}cell = E^{0} Ni^{2+/Ni} - E^{0} S/S^{2-}$
we know that, ${E^{0} Ni^{2+}/Ni = -0.25 v$
and ${E^{0} S/ S^{2-} = -0.47 v$

Therefore, $E^{0} cell$ = - 0.25 - (-0.47) = 0.22 v

Since, $E^{0} cell$ is positive, hence cell reaction is spontaneous
.....................................................................................................................

Answer 2:
Consider reaction: Pb^2+ (aq) +H2 (g) ----> Pb (s) +2H^+ (aq)

The cell representation of above reaction is given by;
 $H_{2} / H^{+} // Pb^{2+} /Pb$

Hence, $E^{0}cell = E^{0} Pb/Pb^{2+} - E^{0} H_{2}/H^{+}$
we know that, ${E^{0} Pb^{2+}/Pb = -0.126 v$
and ${E^{0} H_{2}/ H^{+} = -0 v$

Therefore, $E^{0} cell$ = - 0.126 - 0 = -0.126 v

Since, $E^{0} cell$ is negative, hence cell reaction is non-spontaneous.

....................................................................................................................

Answer 3:
Consider reaction: 2Ag^+ (aq) + Cr(s) ---> 2 Ag (s) +Cr^2+ (aq)

The cell representation of above reaction is given by;
 $Cr/Cr^{2+} // Ag^{+}/Ag$

Hence, $E^{0}cell = E^{0} Ag^{+}/Ag - E^{0} Cr/Cr^{2+}$
we know that, ${E^{0} Ag^{+}/Ag = -0.22 v$
and ${E^{0} Cr/ Cr^{2+} = -0.913 v$

Therefore, $E^{0} cell$ = - 0.22 - (-0.913) = 0.693 v

Since, $E^{0} cell$ is positive, hence cell reaction is spontaneous

8 0

4 years ago

Read 2 more answers

Select the correct answer. Based on the reactivities of the elements involved, which reaction will form products that are more s

FinnZ [79.3K]

Answer: The correct answer is option B.

Explanation: Reactivity of elements is defined as the tendency to loose or gain electrons.

These reactions are a type of single displacement reactions. A single displacement reaction is a type of reaction in which an element displaces another element in a chemical reaction. These are studied with the help of reactivity series.

The element which lies above in the reactivity series can easily displace the element which lies below in the reactivity series.

Option A: This reaction will not yield a stable product because Zinc lies below Aluminium in the reactivity series.

$AlBr_3+Zn\rightarrow \text{No reaction}$

Option B: This reaction will yield a stable product because Sodium lies above Calcium in the reactivity series.

$CaBr_2+2Na\rightarrow 2NaBr+Ca$

Option C: This reaction will not yield a stable product because Hydrogen lies below Magnesium in the reactivity series.

$MgBr_2+H_2\rightarrow \text{No reaction}$

Option D: This reaction will not yield a stable product because Calcium lies below Barium in the reactivity series.

$BaBr_2+Ca\rightarrow \text{No reaction}$

Option E: This reaction will not yield a stable product because barium lies below Lithium in the reactivity series.

$2LiBr+Ba\rightarrow \text{No reaction}$

8 0

4 years ago

A description of a material that scatters light that passes through it

Nookie1986 [14]

Answer:

triangular prism

Explanation:

triangular prism scatters light through it into 7 spectrum colours , I'm not sure it's the right answer please make sure of it from someone else

4 0

3 years ago

How can mass and energy behave in an open system

algol13

An open system is a system that has external interactions.

3 0

3 years ago