Answer:
Bases (solutions with a high pH) feel slipper, have an -OH group, and are corrosive.
Answer:
If liquid bromine is cooled to form a solid, which type of solid does it form? Brass is made by melting copper and zinc and physically mixing them. As this alloy is cooled, it forms a solid where the copper and zinc are not chemically bonded together.
Explanation:
Dimitri Mendeleev was the first to put elements together on a table. He knew there were elements missing but he noticed a trend in some of the elements known at the time. Sodium, Lithium and other alkali metals all have the same properties so he put them under the same column and created other columns with similar attributes (Halogens, Noble gases, Alkaline earth metals). Over the years, new elements were discovered and put into the rough outline that Mendeleev created.
I hope that is about what you wanted.
Answer:
B
Explanation:
Behaviour therapy was popularized by the U.S. psychologist B.F. Skinner, who worked with mental patients in a Massachusetts state hospital.
A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.
Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).
For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.
Activation energy of reverse and forward reactions is related by:
Activation energy of reverse rxn = Activation energy of forward rxn - ΔH rxn
=> Activiation energy of reverse rxn = 102 kJ/mol - 55 kJ/mol = 47 kJ/mol
Answer: 47 kJ/mol
