How To Questions & Answers | Page 21

The number $70.300722$ is rational because it can be expressed as the fraction $\frac{70300722}{1000000}$.

No, there is no material with perfect resistance to electricity; even the best insulators allow a negligible amount of current, as described by $V = IR$.

Given that an angle measures $36^\circ$ and since it’s less than $90^\circ$, it is classified as an acute angle.

The acid test helps determine if a mineral is a carbonate, as carbonate minerals react with hydrochloric acid (HCl) to produce carbon dioxide gas (CO₂) and effervescence.

Chocolate candy melts in your hand because the heat from your body (approximately 37°C or 98.6°F) is higher than the melting point of chocolate (30°C to 32°C or 86°F to 90°F), causing the cocoa butter to transition from solid to liquid.

Substances with London dispersion forces are the least soluble because the weak intermolecular attractions do not substantially overcome the cohesive forces within the solute and solvent, leading to poor dissolution, especially in polar solvents.

The reaction between iron pipes and fertilizer produces corrosive iron compounds, mainly iron oxides, through oxidation, resulting in the formation of rust ($\text{Fe}_2\text{O}_3 \cdot n\text{H}_2\text{O}$).

Shells and corals belong to the Biosphere, interacting significantly with both the Lithosphere and Hydrosphere through processes like the formation of calcium carbonate ($\text{CaCO}_3$).