Basics of Atomic Structure

Q.

Compare the properties of electrons, protons, and neutrons.

Q. Which of the following statements is/are incorrect?

1. Positron has the same mass as that of an electron
2. Positron has the same charge as that of a proton
3. Positron has the same e/m ratio as $\alpha$-particles
4. Emission of a positron results in an increase in the p/n ratio in the daughter nuclide

Q. Boron resembles silicon in properties. This resemblance is mainly due to equal values of:

1. electro negativities of boron and silicon
2. atomic volumes of boron and silicon
3. densities of boron and silicon
4. polarising powers of $B^{3+}andS{i}^{4+}$

Q. The charge on the atom containing $17$ protons, $18$ neutrons and $18$ electrons is :

1. $+1$
2. $-2$
3. $-1$
4. Zero

Q. $[{Fe\left(H_{2}O\right)}_{5}No{]}^{2+}$ is formed as brown ring in ${NO}_3^{+}$ test. $Fe$ in this complex has _________ unpaired electrons.

1. two
2. one
3. three
4. four

Q.

Compare the characteristics of proton, electron, and neutron.

Q. Assertion :In a radioactive disintegration, an electron is emitted by the nucleus. Reason: Electrons are always present inside the nucleus.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. The number of electrons involved in the reaction, when a faraday of electricity is passed through an electrolyte in solution is:

1. $12\times {10}^{46}$
2. $96540$
3. $8\times {10}^{16}$
4. $6\times {10}^{23}$

Q.

Define electron.

Q. Upon irradiating californium with neutrons, a scientist discovered a new nuclide having mass number of $250$ and a half-life of $0.50hr$. Three hours after the irradiation, the observed radioactivity due to the nuclide was $10dis/min$. How many atoms of the nuclide were prepared initially?

Q. Electronegativity of nitrogen is more than phosphorous.

Q. Which of the following statements is/are incorrect?

1. Positron has the same mass as that of an electron
2. Positron has the same charge as that of a proton
3. Positron has the same e/m ratio as $\alpha$-particles
4. Emission of a positron results in an increase in the p/n ratio in the daughter nuclide

Q. Which of the following statements is/are incorrect?

1. Positron has the same mass as that of an electron
2. Positron has the same charge as that of a proton
3. Positron has the same e/m ratio as $\alpha$-particles
4. Emission of a positron results in an increase in the p/n ratio in the daughter nuclide

Q. Which of the following statements is/are incorrect?

1. Positron has the same mass as that of an electron
2. Positron has the same charge as that of a proton
3. Positron has the same e/m ratio as $\alpha$-particles
4. Emission of a positron results in an increase in the p/n ratio in the daughter nuclide