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Charles' law is a special case of the ideal gas law in which the pressure of a gas is constant. Charles's law defines the direct relationship between temperature and volume. GIVEN DATA: V\(_1\) = 29.5cm\(^3\), V\(_2\) = ? , T\(_1\) = 0ºc or 273k, T\(_2\) = 15ºc or 288k \(\frac{V_1}{T_1}\) = \(\frac{V_2}{T_2}\) V\(_2\) = \(\frac{V_1 x T_2}{T_1}\) → \(\frac{29.5 x 288}{273}\) V\(_2\) = 31.1cm\(^3\)

The method used to prepare a salt depend on: the solubility of the salt in water. the heat stability of the salt

If you add salt to water, you lower its freezing point as well as raise its boiling point.

Shells and subshells are filled in energy level order, so electrons will fill the 2p subshell before the 3s shell. And the x subshell before the y and z.

Activated Carbon filters are excellent at removing chlorine and related poor taste and odor.

To make a fixed amount of a dilute solution from a stock solution, use the formula: C\(_1\)V\(_1\) = C\(_2\)V\(_2\) where: V\(_1\) = Volume of stock solution needed to make the new solution. C\(_1\) = Concentration of stock solution. V\(_2\) = Final volume of new solution. C\(_2\)= Final concentration of stock solution 2 * 10 = 0.5 * V2 20 = 0.5V2 \(\frac{20}{0.5}\) = V2 V\(_2\)= 40dm\(^3\) What would be added = V\(_2\) - V\(_1\) = 40 - 10 = 30dm\(^3\)

Since 2 mol H\(_2\) reacted with 1 mol of O\(_2\) : 50cm\(^3\) of hydrogen reacted with 25cm\(^3\) of oxygen Remainder oxygen = Supplied amount - Reacted amount → 75cm\(^3\) - 25cm\(^3\) = 50cm\(^3\)

The arrangement of elements in order of increasing electrode potential values is called electrochemical series. K > Na > Ca > Mg > Al > Zn > Fe > Ni > Sn > Pb > H > Cu > Ag > Au.

The steel spoon to be coated with silver is the cathode of the electrolytic cell and the anode of the electrolytic cell is made of a silver metal

high temperature and high pressure favor the highest yield for N\(_2\)O\(_4\) high temperature favours the production of the reactant since it is endothermic, while high pressure favours the side involving a decrease in volume.

The enthalpy change of neutralisation involving weak acids are smaller in magnitude compared to that between strong acids and strong bases. This is because weak acids/bases are partially dissociated, which means not all hydrogen ions are free to react with hydroxide ions. For strong acids and bases, the enthalpy of neutralisation values are always closely similar with the values -57 and -58 KJ/mol. We know that strong acids completely ionize in water. In case of weak acids, only partial dissociation of its ions occurs.

An endothermic reaction is any chemical reaction that absorbs heat from its environment.

NaH is a saline (salt-like) hydride, composed of Na+ and H− ions. NaH (sodium hydride) is considered an ionic compound because it is composed of a metal (sodium) and a non-metal (hydrogen), where sodium readily loses an electron to form a positive ion (Na+) and hydrogen gains an electron to form a negative ion (H-) creating an ionic bond between them.

The oxides which neither react with acids nor react with bases are known as neutral oxides. Carbon monoxide neither reacts with acids nor reacts with bases. Thus, carbon monoxide is a neutral oxide, produced when combustion reactions are not fully completed, either through lack of oxygen or due to low mixing

Chlorine is a yellow-green gas at room temperature. Chlorine has a pungent, irritating odor similar to bleach that is detectable at low concentrations. Exposure to low concentrations of chlorine (1 to 10 ppm) may cause eye and nasal irritation, sore throat, and coughing. Inhalation of higher concentrations of chlorine gas (>15 ppm) can rapidly lead to respiratory distress with airway constriction and accumulation of fluid in the lungs (pulmonary edema).