The first step is to write the balanced equation of the dissociation of the monoprotic weak acid. This can be assumed to have 1:1 stoichiometric relationships, so the equation and ICE chart are given by:
HA ---> H^+ + A^-
initial 0.25 0 0
change -x x x
equilibrium 0.25-x x x
This gives an expression for Ka given by:
Ka = (x)^2/(0.25-x) = 5.4x10^-6
x = 1.159x10^-3 = [H+] = [A-]
pH = -log[H+] = -log[1.159x10^-3] = 2.936
Answer:
4.15g
Explanation:
Balance the reaction:
2Mg + O2 = 2MgO
Find limiting reactant from the two, by dividing miles with coefficient
2.5/24.3 = 0.103 moles/2 = 0.0515
5/16 = 0.31 moles/2 = 0.156
0.0515 is small than 0.156, so limiting reactant is Mg
Compare the ratio of Mg with MgO
Ratio is 2:2
So same moles = 0.103 moles
Mass = moles x molar mass of MgO
Mass = 0.103 x 40.3
= 4.15g
*please give brainlest*
Answer: The results of Rutherford's gold foil experiment gave him the evidence to arrive at two conclusions: (1) an atom was much more than just empty space and scattered electrons and (2) an atom consists of a positive charge at the center where most of its mass is placed.
Explanation:
Ernest Rutherford performed an experiment in which he passed alpha particles through a thin gold foil sheet. Through this sheet some of the particles passed on to the other side but some of them were reflected back.
This experiment was done by Rutherford to prove than an atom contains a tiny and heavy nucleus. He concluded that an atom has more than empty space and electrons were present in scattered form.
Also, he concluded that an atom consists of a positive charge at the center where most of its mass is placed.
Thus, we can conclude that the results of Rutherford's gold foil experiment gave him the evidence to arrive at two conclusions: (1) an atom was much more than just empty space and scattered electrons and (2) an atom consists of a positive charge at the center where most of its mass is placed.
In the combustion process using excess oxygen, each mole of methane results to 1 mole of co2 while ethane produces 2 moles of Co2. Under same conditions, these can be translated to volume. Hence the total volume absorbed is 10 cm3 + 20 cm3 = 30 cm3.
The image represents A COMPOUND because the molecules are BONDED CHEMICALLY.
A compound is a substance formed when two or more elements combine together chemically. In the process of chemical combination, the chemical bonds that were present in the participating elements will be broken and new chemical bonds will be formed in the product.
