<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We do as follows:
4.50 mol Fe ( 6.022x10^23 atoms / 1 mol Fe ) = 2.71x10^24 atoms Fe present </span>
I feel like all of them are true
We want to solve Q = mcΔT for the liquid water; its change in temperature will tell us the amount of thermal energy that flowed out of the reaction. The specific heat, c, of water is 4.184 J/g °C.
Q = (72.0 g)(4.184 J/g °C)(100 °C - 25 °C) = 22593.6 J
Q ≈ 2.26 × 10⁴ J or 22.6 kJ (three significant figures).
Covalent bonds are formed between nonmetals.
Components of the Skeletal System. The skeletal system is composed of four main fibrous and mineralized connective tissues : bones, ligaments, tendons, and joints. Bone: A rigid form of connective tissue that is part of the skeletal system of vertebrates and is composed principally of calcium.