Engineering Chemistry- UV- Visible Spectroscopy
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NCERT SOLUTIONS Class 9 Chapter 4
Question 1: Compare the properties of electrons, protons and neutrons. Answer: Electron Proton Neutron Electrons are present outside the nucleus. Protons are present in the nucleus. Neutrons are present in the nucleus of the atom. They are negatively charged. They are positively charged. They are neutral in charge. Mass of electrons is negligible. The mass …
NCERT SOLUTIONS Class 9 Chapter 3
Question 1: A 0.24 g sample of the compound of oxygen and boron was found by analysis to contain 0.096 g of boron and 0.144 g of oxygen. Calculate the percentage composition of the compound by weight. Answer: Mass of boron = 0.096g (Given) Mass of oxygen = 0.144g (Given) Mass of sample = 0.24g …