Rutherford was one of the early scientists who worked on the atomic model. Before his discovery of the nucleus, the widely accepted theory was J.J Thomson's Plum Pudding Model. In this model, all the protons, electrons and neutrons are in the nucleus. But the electrons are more in number such that the electrons act as the 'pudding' and the proton and nucleus the 'plum'. This was Rutherford's hypothesis in his gold foil experiment. In order to test the Plum Pudding model, he hypothesized that when a beam of light is aimed at the atom, it would not diffract because the charges in the nucleus are well-distributed. However, his experiment disproved Thomson's model. Some light indeed passed through but a few was diffracted back to the source. He concluded that this was because there is a dense mass inside the atom called nucleus. Thus, from there on, he proposed the model that the electrons are orbiting around the nucleus.
A)1.75×3 moles of carbon monoxide
B)2:3
A)each mole of ferric oxide requires 3 moles of carbon monoxide. Therefore 1.75 moles requires 1.75 ×3 moles of carbon monoxide
1. Salt is KNO₃<span>
<span>This is a </span>strong acid - strong base<span> <span>reaction. </span></span>HNO</span>₃ is the strong acid<span> <span>and </span></span>KOH is the strong
base<span>. </span><span>
H</span>⁺<span> in the HNO₃<span>
and </span></span>OH⁻<span> <span>of the KOH pair up and make </span></span>H₂O(l)<span>. </span><span>
NO</span>₃⁻<span> <span>and </span></span>K⁺<span> <span>pair up to make </span></span>KNO₃ salt<span>. </span><span>
<span>When writing chemical formulas </span>positive ion comes first<span> <span>and second
is negative ion. The charges should be switched. Since </span></span>positive ion has +1 and negative
ion has -1<span> <span>after
the switching off charges </span>the </span>product should be KNO</span>₃.<span>
Balance
equation is </span><span>
HNO</span>₃<span>(aq) + KOH(aq) → H</span>₂O(l) + KNO<span>₃(aq)</span><span>
<span>
2. Salt is Ca(NO</span></span>₃)₂<span>
</span>This is a strong acid - strong
base<span> reaction. </span>HNO₃ is the strong acid<span> and </span>Ca(OH)₂ is the strong base<span>. </span><span>
<span>
H</span></span>⁺<span> in the HNO₃ and </span>OH⁻<span> of the Ca(OH)₂
pair up and make </span>H₂O(l)<span>. </span><span>
Ca²⁺
and </span>NO₃⁻<span> pair up to make </span>Ca(NO₃)₂ salt<span>. </span><span>
<span>
</span><span>Positive ion is </span>Ca²⁺<span>
which has </span></span>+2 charge<span> and negative ion is</span> NO₃⁻<span> <span>which has </span></span>-1 charge<span>. From switching the charges </span>Ca²⁺ gets 1<span> <span>while </span></span>NO₃⁻ gets 2.<span> Hence, the salt should be </span>Ca(NO₃)₂.<span>
Balanced equation
is
</span>2HNO₃<span>(aq) + Ca(OH)</span>₂<span>(aq) → 2H</span>₂O(l) + Ca(NO<span>₃)₂(aq)</span><span>
<span>
3. Salt is CaCl</span></span>₂<span>
This is a strong acid - strong base<span> reaction. </span>HCl is the
strong acid<span> and </span>Ca(OH)</span>₂ is the strong base<span>. </span><span>
<span>
H</span></span>⁺<span> in the HCl and </span>OH⁻<span> of the Ca(OH)₂
pair up and make </span>H₂O(l)<span>. </span><span>
Ca²⁺
and </span>Cl⁻<span> pair up to make </span>CaCl₂ salt<span>. </span><span>
<span>
</span><span>Positive ion is </span>Ca²⁺
which has </span>+2
charge<span> and negative ion is</span> Cl⁻<span> which has </span>-1
charge<span>. By switching the charges </span>Ca²⁺ gets 1<span> while </span>NO₃⁻ gets 2.<span> Hence, the salt should be </span>CaCl₂.<span>
Balance
equation is
</span><span>2HCl(aq) + Ca(OH)</span>₂<span>(aq) → 2H</span>₂O(l) + CaCl₂<span>(aq)
4. Salt is KCl<span>
</span>This is a strong acid - strong base<span> reaction. </span>HCl is the
strong acid<span> and </span>KOH is
the strong base<span>. </span>
<span>
H</span></span>⁺<span> in the HCl and </span>OH⁻<span> of the KOH pair up and make </span>H₂O(l)<span>. </span><span>
K</span><span>⁺ and </span>Cl⁻<span> pair up to make </span>KCl salt<span>. </span><span>
<span>
</span><span>Positive ion is K</span></span><span>⁺ which has </span>+1
charge<span> and negative ion is</span> Cl⁻<span> which has </span>-1
charge<span>. By switching the charges </span>K⁺ gets 1<span> and </span>Cl⁻ also gets 1.<span> Hence, the salt should be </span>KCl.<span>
Balance
equation is
</span><span>HCl(aq) + KOH(aq) → H</span>₂<span>O(l) + KCl(aq)</span>
Answer:
The right answer is "3 g".
Explanation:
Given:
Initial mass substance,
By using the relation between half lives and amount of substances will be:
⇒ 
Thus, the above is the correct answer.
Combination
Hope this helps :)
