Answer:
D: Carbon
Explanation:
The periodic table lists all the known elements. When looking at it, the only choice you will find is carbon. Therefore, carbon is the element.
Carbon is also by itself, just C.
Water is H2O, which is a molecule due to the 2 different elements.
Carbon Dioxide is CO2, which is a molecule due to the 2 different elements.
Air is just a mixture of different gas molecules, so therefore it is not an element.
Answer:
increase
Explanation:
because in endothermic reaction heat is absorbed
The answer is 27.92g . working is shown in the picture above.
We can use the ideal gas equation:
PV = nRT
P = 202.6kPa = 202600 Pa (You have to
multiply by 1000)
n = 0.050 mole
R = 0.082 atm*l/(K*mol)
T = 400K
We will have to convert from Pa to atm or
viceversa.
101325 Pa________1 atm
202600 Pa________x = 2.00 atm
2atm*V = 0.050 mole*0.082 atm*l/(K*mol)* 400K
V = 0.050 mole*0.082 atm*l/(K*mol)* 400K/2atm
= 0.82 liters = 820 mililiters
