Answer:
Dry ice undergoes sublimation, an endothermic change at room temperature.
Answer:
The reaction must be spontaneous, the disorder of the system increases.
Explanation:
By the Second Law of Thermodynamics, a positive change in entropy is due to a net input heat, and entropy is a measure of the grade of disorder within the system. The net input heat means that resultant goes to the system from the surroundings.
By the First Law of Thermodynamics, a net input heat is due to a positive change in enthalpy.
The reaction is endothermic and spontaneous (since change in entropy is positive).
126 grams of H2O is formed.
Explanation:
Data given:
volume of the gas = 88 Liters
pressure = 720 mm Hg or 0.947 atm
temperature T = 22 Degrees or 295.15 K
R = 0.08021 atm L/mole K
n =?
The formula is used is of ideal gas law to know the number of moles of CH4 undergoing combustion.
PV = nRT
n = 
putting the values in the equation
= 0.947 X 88/ 0.08021 X 295.15
n = 3.5 moles
balanced reaction for combustion of methane
CH4 + O2 ⇒ CO2 + 2H20
1 mole of CH4 undergoes combustion to form 2 moles of water
3.5 moles will give x moles of water
2/1 = x/3.5
x = 7 moles of water (atomic mass of water = 18 gram/mole)
mass = atomic mass x number of moles
mass = 18 x 7
=126 grams of water is formed.
Answer:
So a sodium atom has the electronic configuration 2,8,1 meaning it has 1 electron on its outer shell. It has a neutral charge since the number of electrons is equal to the number of protons.
A sodium ion is one that has lost the electron on its valence shell. The electronic configuration is 2,8 and it has a positive charge because it has more protons than electrons.
Explanation:
Thus, those metals which remain unaffected by moisture, oxygen and carbon dioxide of the air can occur native or free. In other words, the unreactive metals occur in nature in free state because of their low reactivity towards chemical reagents. ... Metals usually occur in combination with nonmetallic elements.