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If delta G standard is zero, the system is at equilibrium at standard conditions. This time the rate of the forward and reverse reaction is the same, and the system is at equilibrium.

First, calculate the total number of number of moles of gaseous species only, on both sides. i.e 1 mole on the LHS while 2 moles on RHS. An increase in pressure will favour the side with the lesser value of the total number of moles while a decrease in pressure will favour the side with the higher number of moles i.e the RHS. Hence,increasing the yield of PCl\(_3\).

A reaction between Iron (iii) chloride and Hydrogen sulphide leads to the reaction 2FeCl\(_3\)(aq) + H\(_2\)S(g) → 2FeCl\(_2\)(aq) + 2HCl(aq) + S(s) The colour change is from REDDISH BROWN to PALE GREEN.

Above is the Arrhenius equation. It is a relationship between speed and activation energy.

When sodium hydroxide dissolves in water, the process is exothermic because the breaking of the ionic bonds in sodium hydroxide releases heat.

Sulphur atom in Cu\(_2\)S is - 2. Thus, Cu\(_2\)S = 0 2Cu + S = 0 2Cu + (-2) = 0 2Cu = 2 \(\frac{2Cu}{2}\) = \(\frac{2}{2}\) Cu = +1 On the RHS, Cu atom has an oxidation state of 0. Therefore, there is a change in oxidation number of Copper from +1 to 0

The products of the electrolysis of dilute sodium hydroxide using platinum electrodes are hydrogen H\(_2\) at the cathode and oxygen (O\(_2\) at the anode. This is because the reduction and oxidation of water occurs to produce hydrogen at the cathode and oxygen at the anode.

At 20oC 0.34 mol/dm of the salt dissolve = 0.34 * 101 = 34.34gm Of the salt dissolved. ∴ 34.34gm dissolve is 1,000cm3 If only 250 cm3 is the required mass X = (250/1000) * 34.34 = 8.555gm If only 3.40gm of the salt dissolved ,the solution is unsaturated

Tetraoxosulphate (VI) acid is highly corrosive and causes damage by tissue dehydration and heat production. Dark-brownish colored burns are usually observed

A salt that contains water of crystallization is called a hydrated salt. The water molecules attached to the salt are called water of crystallization. When a hydrated salt is exposed to air, it can lose its water of crystallization through evaporation. This process is called efflorescence.

First, write a balanced chemical equation or the reaction: Na\(_2\)CO\(_3\) + 2HCl → 2NaCl + H\(_2\)O + CO\(_2\) From the balanced equation, we can deduce that N\(_A\) = 2 , N\(_B\) = 1 We were also given from the question, C\(_A\) = ? C\(_B\) = 0.2 mol/dm\(^3\) V\(_A\) = 20cm\(^3\) V\(_B\) = 25 cm\(^3\) Using the relationship, \(\frac{C_A V_A}{C_B V_B}\) = \(\frac{N_A}{N_B}\) C\(_A\) = \(\frac{C_B V_B N_A}{V_A N_B}\) C\(_A\) = \(\frac{0.2 X 25 X 2}{20 X 1}\) = 0.5 mol/dm\(^3\)

Lead compounds, Organophosphorous compounds, and Uranium are considered as sources of pollution to the environment while Silicate minerals such as quartz, beryl, feldspar etc causes little impactation on the environment in terms of pollution.

The property that makes alcohol soluble in water is hydrogen bonding, which occurs between the hydroxyl group in alcohol and water molecules. The hydroxyl group in alcohol is hydrophilic, meaning it's "water-loving". This group forms hydrogen bonds with water molecules, which makes alcohol soluble in water.

Steam changes the color of anhydrous cobalt (II) chloride from blue to pink.

In the brown ring test, nitric oxide (NO) is produced when acidified iron (II) sulphate reacts with dilute nitric acid. The nitric oxide then reacts with iron (II) to form a complex ion, which creates a brown ring at the junction of the two liquids.