Answer: fixed shape and volume
Explanation:
i took the quiz so its right
There are many ways to predict the properties of an element here's one example.As you move from left to right the electron affinity and ionization energy both increase .Since elements of the same family have similar characteristic,you can often predict the properties of another element in its family
Answer:
The cell membrane's main trait is its selective permeability, which means that it allows some substances to cross it easily, but not others. Small molecules that are nonpolar (have no charge) can cross the membrane easily through diffusion, but ions (charged molecules) and larger molecules typically cannot. A concentration gradient is a just a region of space over which the concentration of a substance changes, and substances will naturally move down their gradients, from an area of higher to an area of lower concentration.
In cells, some molecules can move down their concentration gradients by crossing the lipid portion of the membrane directly, while others must pass through membrane proteins in a process called facilitated diffusion.
Explanation:
there are your two reasons molecules cannot pass easily through the cell membrane and what part of the cell membrane helps them get through is concentration gradient
Zirconium cannot be broken down by a chemical change, because it is an element. The others are all molecules.
Answer:
4054 kcal of heat is released during complete combustion of 354 g of octane.
Explanation:
Heat of combustion of 1 mol of octane is 
kcal
Molar mass of octane = 114.23 g/mol
We know, no. of moles = (mass)/(molar mass)
So, kcal of heat is released during complete combustion of 114.23 g of octane.
So, amount of heat is released during complete combustion of 354 g of octane = 
kcal = 4054 kcal
Hence 4054 kcal of heat is released during complete combustion of 354 g of octane.
