Answer:
Convection?
Explanation:
The circulation of heat currents?
The reaction is
2Cu + S → Cu2S
So as per balanced given reaction we need one mole of sulphur over two moles of copper
Or
To react with one mole of sulphur we need two moles of copper
Thus we can say that the mole ration required for complete reaction will be
Cu : S = 2 : 1
As per the given problem the moles of each Cu and S are 3 moles
Thus for each three moles of given sulphur we need six moles of Cu to give three moles of Cu2S
However we have only three moles of copper available
So the limiting reagent is copper
It is going to decide the actual yield of reaction
The three moles of Copper will get completely utilized and only 1.5 moles of S will be used in the reaction making S an excess reagent
The moles of S left will be = 1.5 moles
moles of Cu2S formed = 1.5 moles
Hydrogen peroxide is one of the most common bleaching agents. It is the primary bleaching agent in the textile industry, and is also used in pulp, paper, and home laundry applications.
bleaching agent is a material that lightens or whitens a substrate through chemical reaction. The bleaching reactions usually involve oxidative or reductive processes that degrade color systems. These processes may involve the destruction or modification of chromophoric groups in the substrate as well as the degradation of color bodies into smaller, more soluble units that are more easily removed in the bleaching process. The most common bleaching agents generally fall into two categories: chlorine and its related compounds (such as sodium hypochlorite) and the peroxygen bleaching agents, such as hydrogen peroxide and sodium perborate. Reducing bleaches represent another category. Enzymes are a new category of bleaching agents. They are used for textile, paper, and pulp bleaching as well as for home laundering. Chlorine‐containing bleaching agents are the most cost‐effective bleaching agents known. They are also effective disinfectants, and water disinfection is often the largest use of many chlorine‐containing bleaching agents. They may be divided into four classes: chlorine, hypochlorites, N‐chloro compounds, and chlorine dioxide. Except to bleach wood pulp and flour, chlorine itself is rarely used as a bleaching agent. The principal form of hypochlorite produced is sodium hypochlorite. Other hypochlorites include calcium hypochlorite and bleach liquor, bleaching powder and tropical bleach. The principal solid chlorine bleaching agents are the chlorinated isocyanurates, eg, sodium dichloroisocyanurate dihydrate. Other N‐chloro compounds include halogenated hydantoins, and sodium N‐chlorobenzenesulfonamide (chloramine B). Chlorine dioxide is a gas that is more hazardous than chlorine. Large amounts for pulp bleaching are made by several processes in which sodium chlorate is reduced with chloride, methanol, or sulfur dioxide in highly acidic solutions by complex reactions. Hydrogen peroxide is one of the most common bleaching agents. It is the primary bleaching agent in the textile industry, and is also used in pulp, paper, and home laundry applications. Hydrogen peroxide reacts with many compounds, such as borates, carbonates, pyrophosphates, sulfates, etc, to give peroxy compounds or peroxyhydrates. Peracids have superior cold water bleaching capability versus hydrogen peroxide because of the greater electrophilicity of the peracid peroxygen moiety. Lower wash temperatures and phosphate reductions or bans in detergent systems account for the recent utilization and vast literature of peracids in textile bleaching. The reducing agents generally used in bleaching include sulfur dioxide, sulfurous acid, bisulfites, sulfites, hydrosulfite (dithionites), sodium sulfoxylate formaldehyde, and sodium borohydride. These materials are used mainly in pulp and textile bleaching.
The value for ΔG = 18 kJ/mol
<h3>Further explanation</h3>
Given
ΔH = 27 kJ/mol and ΔS = 0.09 kJ/mol.K
T = 100 K
Required
the value for ΔG
Solution
The spontaneous process of a reaction is based on 2 factors :
- enthalpy change ΔH decreases and
- entropy change ΔS increases
ΔG=ΔH-T.ΔS
Gamma rays consist of pure energy. Beta particles consist of one electron that is released at high speeds from an unstable nucleus and an alpha particle is a helium nucleus.
We know that Gamma rays consist of pure energy because, during Gamma decay, the atomic and mass numbers remain unchanged. Therefore, only energy is emitted.
Gamma rays are weakly ionising, however, they are strongly penetrating and thick concrete or a few centimetres of aluminium is needed to stop them.
