Answer:
Metals have an important role in our daily life. The discovery of the metal is said to be the most important milestone in the history of human civilization. We cannot live without machines now. All machines are made up of metals. Machines reduce the work of man. Many modern facilities would not have been possible without metals. Most metals occur as their compounds in nature.
Answer:
V ∝ n
Step-by-step explanation:
Suppose that pressure and temperature are constant.
If you try to force more molecules of air into a balloon, the balloon will expand.
This is an example of <em>Avogadro's Law</em>: the volume of a gas is directly proportional to the number of moles (particles).
V ∝ n
Answer:
a. pH = 2 b. pH = 3 c. pH = 1 d. Unanswerable
Explanation:
pH = -log[H+] OR pH = -log{H3O+]
and inversely
pOH = -log[OH-]
1. Determine what substance you are working with, (acid/base)
2. Determine whether or not that acid or base is strong or weak.
a. 1.0 x 10^-2M HCl
HCl is a strong acid, therefore it will dissociate completely into H+ and Cl- with all ions going to the H+, therefore, the concentration of HCl and concentration of H+ are going to be equal, meaning we simply take the negative logarithm of the concentration of HCl and that would equal pH
pH = -log[H+]
pH = -log(1.0x10^-2)
pH = 2
b. 1.0 x 10^-3M HNO3
HNO3 like part a, is a strong acid, therefore it would simply require you to take the negative logarithm of the concentration of the compound itself, to find its pH.
pH = -log[H+]
pH = -log(1.0 x 10^-3)
pH = 3
c. 1.0 x 10^-1M HI
Like the previous parts, HI is a strong acid
pH = -log[H+]
pH = -log(0.10)
pH = 1
d. HB isn't an element, nor is it a compound so that would be unanswerable.
In chemical reactions, the actual yield is not the same as the expected yield . Actual yield is lower than the theoretical yield . Then we have to find the yield percentage. To see what percentage of the theoretical yield is the actual yield.
Percent yield = actual yield / theoretical yield x 100%
Percent yield = 24.6/55.9 x100%
Percent yield = 44%
Answer:
0.07172 L = 7.172 mL.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.
</em>
where, P is the pressure of the gas in atm (P = 1.0 atm, Standard P).
V is the volume of the gas in L (V = ??? L).
n is the no. of moles of the gas in mol (n = 3.2 x 10⁻³ mol).
R is the general gas constant (R = 0.0821 L.atm/mol.K),
T is the temperature of the gas in K (T = 273 K, Standard T).
<em>∴ V = nRT/P =</em> (3.2 x 10⁻³ mol)(0.0821 L.atm/mol.K)(273 K)/(1.0 atm) = <em>0.07172 L = 7.172 mL.</em>