Answer:
B.Bronze is harder than copper, so it retains a cutting edge sharper than that of copper.
Explanation:
The importance of bronze in the history of the human kind can not be only measured in the durability but the help that it provided to our ancestors, the things they were allowed to do once they dicovered how to mold it, and the tools that they produced and made many every day tasks easier for them and the ability of bronze to mantain the cutting edge longer than copper was one of the main reasons why it took its places in the fabrication of many tools.
The reaction must be a + b --> c
Then you can predict a reaction rate, r o the type r = k * a^n * b^m
Given that the reaction rate is not affected by the concentration of b you can state that m = 0 and r = k * a^n.
Now given, that there is a proportional relation between the reaction rate and a (double a gives double rate), then n = 1 and r = k*a. You can verify that if you dobule a r also doubles.
Answer: r = k*a
To determine the amount of 6.0 M H2SO4 needed for the preparation, equate the number of moles of the 6.0 M and 2.5 M H2SO4 solution. This is done as follows
M1 x V1 = M2 x V2
Substituting the known variables,
(6.0 M) x V1 = (2.5 M) x (4.8 L)
Solving for V1 gives an answer of V1 = 2 L. Thus, to prepare the needed solution, dilute 2 L of 6.0 M H2SO4 solution with water until the volume reach 4.8 L.
Answer: a.
:
is negative
b.
:
is negative
c.
:
is negative
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa
a) 
In this reaction 2 moles of gaseous reactants are converting to 1 mole of gaseous products. The randomness will decrease and hence entropy will also decrease. Thus
is negative.
b) 
In this reaction solid reactants are converting to aqueous products. The randomness will increase and hence entropy will also increase. Thus
is positive.
c) 
In this reaction aqueous reactants are converting to solid products. The randomness will decrease and hence entropy will also decrease. Thus
is negative