The standard heat of formation is the energy change that occurs when 1 mole of a substance is made from its elements in their standard states ( most stable form of the element at 1 bar of pressure and the specified temperature, usually 298 K or 25 degrees Celcius)
E.g for MgCO3
Mg (s) + C (s) + 3/2 O2 (g) = MgCO3
Groundwater varies between each year and state. Although from this map it seems as though the southeast part of the US contains more groundwater than other states. While the southwest and west side of the US does not contain as much groundwater as other states.
Answer:
a. The new pressure is 606,25 Torr.
b. -243,9°C is needed to reach the pressure of 7250 Torr.
Explanation:
Gay Lussac's law for gases says that if the volume in a gas remains constant, the pressure will be directly proportional to the temperature change.
P1 . T1 = P2. T2
(Temperature must be in K)
725 Torr . 291 K = P2 . 348 K
(725 Torr . 291 K) /348 K = P2
606,25 Torr = P2
725 Torr . 291K = 7250 Torr . T2
(725 Torr . 291K) /7250 Torr = T2
29,1 K = T2
T° K - 273 = T°C
29,1 K -273 = -243,9°C
Answer:
C. transition elements
Explanation:
Transition elements are groups of metallic elements that have partially filled d orbitals. They occupy the d-block of the periodic table (Group 3-12). Examples of elements that fall under this category are Nickel (Ni), Cobalt (Co), Copper (Cu), Zinc (Zn) etc. Transition metals have outstanding properties that distinguishes them from other elements.
One of these properties is their ability to form colored compounds due to their unfilled d electron shells. They form ions that are usually colored in solid compounds and in solution.
