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Questions in chemistry

[Done] Hydrangea plant's petals change to which color upon the addition of acids?

[Done] Bombarding sodium-23 with a proton produces nuclide X and a neutron. What is nuclide X? A. magnesium-24 B. magnesium-23 C. neon-23 D. sodium-24 E. none of the above --- The isotope P has a half-life of 14.3 days. If a sample originally contained 1.00 g of P, how much was left after 43 days? A. 0.250 g B. 0.125 g C. 0.750 g D. 0.500 g --- Identify X in the reaction below: \[ \text{U} + \text{C} \rightarrow \text{Cf} + X \] A. 1 alpha particle B. 3 protons C. 6 neutrons D. 6 electrons --- A 0.20 gram sample of C-14 was allowed to decay for 3 half-lives. What mass of the sample will remain? Carbon-14 has a half-life of 5730 years. A. 0.025 g B. 0.05 g C. 0.1 g D. 0.01 g --- The isotope Cu has a half-life of 30 s. If a sample originally contained 48 mg of Cu, how much time passed before the amount fell to 3 mg? A. 120 s B. 240 s C. 30 s D. 60 s --- What radionuclide decays to Fe-56 by beta emission? A. Fe B. Co C. Mn D. Co E. Mn --- The Cf to Cf conversion is accompanied by __________. A. an alpha emission B. a neutron capture C. an electron capture D. an electron release

[Done] Iron nails do not get rusted when kept in distilled water even for a long time. Give a reason.

[Done] What is hydrolysis?

[Done] What is NADPH\(_2\)? Where is it used?

[Done] Name two salts used in black and white photography.

[Done] Name the type of chemical reaction: \[ \text{CaO}(s) + \text{H}_2\text{O}(l) \rightarrow \text{Ca(OH)}_2(aq) \]

[Done] What is the percent yield of ferrous sulfide if the actual yield is 220.0 g and the theoretical yield is 275.6 g?

[Done] Are all metals acidic in nature and all non-metals basic? What is the nature of their oxides?

[Done] Why are only nitrogen and argon gases used in light bulbs?