Answer:
ΔH = 180.6 kJ
Explanation:
Given that:
N2 (g) + 2O2(g) = 2NO2 (g) ΔH = 66.4 kJ
<u>2NO (g) + O2 (g) = 2NO2 (g) ΔH = -114.2 kJ </u>
N2 (g) + O2 (g) = 2NO (g) ΔH = ????
The subtraction of both equations would yield the unknown ΔH , therefore:
ΔH = 66.4 - ( - 114.2 kJ)
ΔH = 180.6 kJ
The isotopes of an element differ in the number or neutrons whereas the number of protons or electrons of a neutral atom stays the same. The molar mass of the element is based on the percent abundances of different isotopes and the individual molar mass of each isotope.
Open system is a system in which mass or energy can be lost to or gained from the environment. In this case, water and power come from external sources best explains why a washing machine would be considered an open system.
Density = Mass / Volume
V = 1.00 * 4.00 * 2.50 = 10 cm³
22.57 g/cm³ = Mass / 10 cm³
M = 22.57 g/cm³ * 10 cm³
M = 225.7 g
Answer: The mass of the block of osmium is 225.7 g.
Answer:
the mass number
Explanation:
Isotopes are numerous forms of one single element. In simple terms, atomic weights are different for the isotopes. Isotopes refer to the atoms that have the same number of protons but different neutron numbers. The physical properties of the isotopes vary because these properties also based on mass. These variations can be used to distinguish isotopes of an element from each other by applying methods such as fractional distillation and diffusion.