The following lab results were obtained when iron was strongly heated in the presence of excess oxygen.?
the following lab results were obtained when iron was strongly heated in the presence of excess oxygen. What is the empirical formula of the metallic oxide? Assume the iron did not react with atmospheric N2 Mass of empty crucible and cover- 70.0000 g Mass of empty crucible and cover and iron (before combustion)- 75.0522 g Mass of empty crucible and cover and iron (after combustion)- 78.9119 g
What will be produced when a mixture of ethanol and concentrated sulphuric acid is heated to a temperature of 170 degree celcius?
Ethylene (ethene, C2H4) will be formed by dehydration when a mixture of ethanol and conC.H2SO4 is heated to 170 degree. It is an alkene having the structural formula H2C=CH2.C2H5OH (+ conc.H2SO4) = C2H4 + H2OAt 14o degree celcius, the main product would be diethyl ether.
When hydrogen gas is passed over heated copper (II) oxide, copper and steam are formed. What's the balanced chemical equation with physical states for this reaction?
sometimes develop your own equations in a step by step manner. it’ll never go wrong. just follow the steps one by one.first write the equation;2H + CuO → Cu + H2O.Now balance the equation. [i m directly doing above].and we know the physical states don’t we?you’ve mentioned it yourself.2H(g) + CuO(s) → Cu(s) + H2O (g).CuO and Cu can niether be in g nor in l state.because:you're heating the whole thing. thus aq. state isn’t possible.you've mentioned H gas and steam.metals need great melting point to become liquid and so does CuO (although not that great).so you see, doing it one by one never goes wrong.
Chemistry?!! Benedicts Reagent effect on Starch and water...? Please Hurry!!! I need an answer!?
Benedict's Reagent (also called Benedict's solution or Benedict's test) is a reagent named after an American chemist, Stanley Rossiter Benedict. It is used as a test for the presence of reducing sugars such as glucose, fructose and maltose, or more generally for the presence of aldehydes (except aromatic ones). It is often used in place of Fehling's solution. Benedict's reagent contains blue copper(II) sulfate (CuSO4) which is reduced to red copper(I) oxide (Cu2O) by aldehydes, also oxidizing them to carboxylic acids. The copper(I) oxide is insoluble in water and so precipitates. Benedict's reagent can be made from 100 g sodium carbonate and 173 g sodium citrate dissolved in 850 mL water, to which a solution of 17.3 g copper(II) sulfate in 100 mL of water is slowly added, and the overall reagent made up to 1 litre. To test for the presence of reducing sugars in food, the food sample is dissolved in water and about 5ml of the sample solution is added to 5ml of Benedict's reagent. The mixture is placed in a boiling water bath for 5 minutes and any precipitate formed is recorded as a positive result for the presence of reducing sugars in the food. Sucrose (household sugar) is a non-reducing sugar and thus does not react with Benedict's reagent. Benedict's reagent can be used to test for the presence of glucose in urine. Glucose found to be present in urine is an indication of diabetes. 5ml of Benedict's reagent is mixed with 0.5ml of urine and the mixture is put in a boiling water bath for 5 minutes. Test On Starch: Starch is a complex carbohydrate which is insoluble in water; it is used by plants as a way to store excess glucose. Starch is by far the most important of the polysaccharides. As the starch does not contain aldehyde group present it will not give positive result with the Benedict Reagent.
What happen when we pass heat to lead nitrate?
When solid lead nitrate is heated strongly a it turns yellow due to formation of lead oxide and a reddish brown gas is evolved which is nitrogen dioxide .When the evolved gas is passed over wooden glowing splinters it rekindles.This shows the presence of oxygen.Hence the Chemical equation for above reaction is-2Pb(NO3)2→2PbO+4NO2+O2
What happens when anhydrous copper sulphate is heated?
Crystal of Copper sulphate holds 5 molecules of water. When it is heated ,the water is evaporated ,greyish white powder of copper(ll) sulphate is formed.CuSO4.5 H2O gives ——→ CuSO4 + 5H2Owhen anhydrous CuSO4 is heated, copper(ll)oxide & sulphur trioxide is formed.CuSO4 (s) ———->CuO (s) + SO3 (g).
What will be the colour of FeSO4 after being heated?
When ferrous sulphate crystals[FeSO4.7H2O] are heated, water of crystallization is lost. And then the anhydrous salt decomposes to form red brown ferric oxide [Iron(III)] , sulphur dioxide (SO2) and sulphur trioxide (SO3) gases.Reactions involved are:Colour of FeSO4. 7H2O (Reactant)—Colour of Fe2O3(product) , end product of thermal decomposition of ferrous sulphate crystals —Method and setup of experiment:This process of heating ferrous sulphate crystals is known as Thermal Decomposition.Thank youHope, it will help:)
Why the oxalic acid solution is heated before titration with KMnO4 solution?
We heat the titration flask containing oxalic acid to about 60-70 degree Celsius and then titrate it against KMnO4. [As a rule, the temperature should be in b/w 60-70 degrees C.]1) All reactions require activation energy and the correct orientation. If you do not heat the mixture, the reactants won't have enough activation energy (in a short time) to start the reaction even they are in the correct orientation. However, if you heat, the heat energy gained by particles convert it to kinetic energy, so they move with higher speed. This results in higher frequency of collision among the particles, so, increased frequency of effective collision. Thus, rate of reaction increases and you will be able to obtain your results in a shorter time. ( Effective collision means success of reaction, i.e. products formed)2) If the temperature is too low (below 55 degrees celsius), the interaction between the oxalate and the potassium permangante will move too slow as to be used as a practical lab experiment.3) Above 60 degrees celsius, oxalate acid begins to decompose, so its important to stay in this range. areound 100 degree celcius, Oxalic acid may decompose to give CO2 & CO.
What happen to lead oxide when heated?
There are two oxides for lead. One is lead(II) oxide, another one is lead (IV) oxide. Lead (IV) oxide is thermally unstable and it tends to decompose into lead(II) oxide and oxygen upon heating.[math]2PbO_2 \rightarrow 2PbO +O_2[/math]Whereas when lead(II) oxide is heated to around 450-480 °C, it forms lead(II,IV) oxide, also known as red lead or triplumbic tetroxide.[math]6PbO + O_2 \rightarrow 2 Pb_3O_4[/math]If it is heated above 480 °C, reverse reaction will occur.[math]2 Pb_3O_4\rightarrow 6PbO + O_2 [/math]