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This is one of our many quizzes on Isotopes. Click on this to access more such competitive quizzes on Physical Chemistry.

Isotopes Quiz 2

chemistry

 Deuterium is one of the isotopes for hydrogen. Find the molecular formula of the deuterium oxide among the given options?

 Water has a molecular formula of ${{H}_{2}}O$ , even the hydrogen atoms are replaced with deuterium; the molecular formula of the chemicals is not going to change. 

By replacing the hydrogen atoms in water with deuterium, the molecular formula of water is going to change to ${{D}_{2}}O$. Only two deuterium are going to replace the hydrogen and the oxygen will be as usual. 

 In NMR spectroscopy deuterated chloroform is going to be used as a solvent to dissolve the organic samples instead of chloroform to decrease the coupling of the proton in chloroform with the protons of the organic compounds. The molecular formula of the deuterated chloroform is?

 The deuterated chloroform is not going to give any peaks in the NMR spectrum of the due to the absence of the proton in the deuterated chloroform. 

&nbsp;Deuterium is going to react with hydrogen in the chloroform and forms deuterated chloroform as a product. The molecular formula of deuterated chloroform is $CDC{{l}_{3}}$

 An element X is bombarded with alpha particles and the substances produced are $_{8}{{O}^{17}}$ and $_{1}{{H}^{1}}$. What can be the starting isotope?<img  src="https://cmds-vedantu.s3.ap-southeast-1.amazonaws.com/prod/question-sets/9487414c-a665-47d1-8e61-57bcd7ab09072975404128218044611.png"/>

 In an $\alpha $ decay, the parent nucleus is converted to $_{A-2}{{N}^{M-4}}$ and there is also formation of $_{2}H{{e}^{4}}$.

 We individually add up the atomic number and mass number to match with the element. The atomic number of unknown elements is $8+2=10$, and the mass number is $17+4=21$, so we get an answer as $_{10}{{X}^{21}}$.

 Which of the following pairs have the same number of electrons?

 The pairs which have the same number of electrons are called isoelectronic species.

 Number of electrons in $CO=6+8=14$, and for nitrogen molecules, we have $7+7=14$, both are the same.

 Solubility curve gives us relationships between?Find the product ‘A’ in the following chemical reaction.<br>$_{92}{{U}^{238}}\to A{{+}_{2}}H{{e}^{4}}$ 

 When a radioactive element is going to decay an alpha particle then the mass number of the daughter element is going to decrease by 4 units and the atomic number is going to decrease by two units.

 Uranium-238 undergoes alpha particle decay and forms thorium -234 as a daughter element. We can see the radioactive decay of U-238 in the following chemical equation. <br>$_{92}{{U}^{238}}{{\to }_{90}}T{{h}^{234}}{{+}_{2}}H{{e}^{4}}$