Question

in - class problems: week 14
(include last names!)
name: _honay ortiz
name: _cedryo pagaringan
name: _tessico
name: _rochel prashant
name: _tackie earmery
name: _t.ei

1. using the graph given to the right regarding the

metal activity series, determine whether the
following reactions will proceed spontaneously.
circle the reactions that will be spontaneous.
a. ( zn_{(s)}+cd^{+2}_{(aq)}
ightarrow cd_{(s)}+zn^{+2}_{(aq)} )
b. ( mg_{(s)}+2k^{+}_{(aq)}
ightarrow 2k_{(s)}+mg^{+2}_{(aq)} )
c. ( co_{(s)}+2h_{2}o_{(l)}
ightarrow h_{2(g)}+co(oh)_{2(aq)} )
d. ( ni_{(s)}+2hcl_{(aq)}
ightarrow h_{2(g)}+nicl_{2(aq)} )

1. in the following reaction,

Explanation:

Step1: Analyze reaction a

In reaction \(a\): \(Zn_{(s)}+Cd^{2 +}_{(aq)}\to Cd_{(s)}+Zn^{2+}_{(aq)}\), check the metal activity series. \(Zn\) is above \(Cd\) in the metal activity series. A more active metal (\(Zn\)) can displace a less active metal (\(Cd\)) from its salt solution. So this reaction is spontaneous.

Step2: Analyze reaction b

In reaction \(b\): \(Mg_{(s)}+2K^{+}_{(aq)}\to 2K_{(s)}+Mg^{2+}_{(aq)}\), \(K\) is above \(Mg\) in the metal activity series. A less active metal (\(Mg\)) cannot displace a more active metal (\(K\)) from its salt solution. So this reaction is non - spontaneous.

Step3: Analyze reaction c

In reaction \(c\): \(Co_{(s)}+2H_{2}O_{(l)}\to H_{2(g)}+Co(OH)_{2(aq)}\), \(Co\) is below \(Mg\) (which reacts with water) in the metal activity series. Metals like \(Co\) do not react with water under normal conditions. So this reaction is non - spontaneous.

Step4: Analyze reaction d

In reaction \(d\): \(Ni_{(s)}+2HCl_{(aq)}\to H_{2(g)}+NiCl_{2(aq)}\), \(Ni\) is above \(H_{2}\) in the metal activity series. Metals above \(H_{2}\) in the series can react with acids (\(HCl\) here) to produce \(H_{2}\). So this reaction is spontaneous.

Answer:

Circle reactions \(a\) and \(d\).