The ideal gas law is: PV=nRT
Pressure
Volume
n= moles
R= gas constant
Temperature in Kelvin
(Degrees in celsius +273)
n= PV/RT
(1.00atm)(5.00L)/(.08026)(295K)= .207mol of gas
Answer: Alkali metals, group 1
Explanation: Group 1 means 1 valence electron. This group is called alkali metals, which indicates that it is a metal. They are highly reactive because only 1 electron needs to move to bond with something (since it only has 1 valence electron)
Answer:
Explanation:
Polyatomic ions are ions (usually anions) that are made up of more than one atom. In order to determine the charge of anions, one can first identify the charge of the metal (which forms the cation) in a compound (which is usually easy to know) before predicting the charge of the anion. The charges are usually exchanged to form denominator of the other reacting atom/molecule, but if divisible, they are divided first before the exchange.
(a) The polyatomic ion in KNO₂ is NO₂ with the ionic equation below showing it's charge
KNO₂ ⇒ K⁺ + NO₂⁻
From the above, we can deduce that the charge of NO₂ is "1-"
(b) The polyatomic ion in CaSO₄ is SO₄ with the ionic equation below showing it's charge
CaSO₄ ⇒ Ca²⁺ + SO₄²⁻
The charge of SO₄ from the above equation is "2-"
(c) The polyatomic ion in Mg(NO₃)₂ is NO₃ with the ionic equation below showing it's charge
Mg(NO₃)₂ ⇒ Mg²⁺ + NO₃⁻
From the above equation, it can be deduced that the charge of NO₃ is "1-"
Answer:
The answer is (3) 1676 kJ. The heats of reaction at 101.3 kPa and 298 K for reaction: 4Al(s) +3O2(g)= 2Al2O3(s) is -3351 kJ. So for one mole of aluminum oxide is 3351/2=1676 kJ.
