1. Which form of energy changes in chemical reactions due to bonds breaking and forming? (1 point) activation
potential
thermal
kinetic

2. What does it mean for a reaction to release energy? (1 point)

The relative potential energy of the reaction is positive.
The relative potential energy of the reaction is negative.
The activation energy of the reaction is positive.
The activation energy of the reaction is negative.

3. Heat is added to a chemical system. Which energy will increase? (1 point)

the relative potential energy of the system
the potential energy of the products
the activation energy of the system
the kinetic energy of the reactant molecules

4. Carbon monoxide and nitrogen monoxide react to produce carbon dioxide and nitrogen gas. If the system contains platinum, then less energy is required for the reaction to occur. Which term best describes the role of platinum in the system? (1 point)

reactant
energy
product
catalyst

5. The two oxygen atoms in a molecule of oxygen gas share their outer electrons. Which type of bond do the oxygen atoms form? (1 point)

ionic
exothermic
endothermic
covalent

1. list three scientific reasons cockroaches may fly.

Nconcentration refers to the molar concentration of an ion in solution. it may be identical to, or greater or less than, the molar concentration of the compound containing the ion that was used to make the solution. for soluble salts, the molarity of a particular ion is equal to the molarity of that compound times the subscript for that ion. for example, 1 m of alcl3 is 1 m in al3+ and 3 m in cl−. 1 m of (nh4)2so4 is 2 m in nh4+ and 1 m in so42−. part a what is the concentration of k+ in 0.15 m of k2s? view available hint(s) nothing m m part b if cacl2 is dissolved in water, what can be said about the concentration of the ca2+ ion? view available hint(s) if is dissolved in water, what can be said about the concentration of the ion? it has the same concentration as the cl− ion. its concentration is half that of the cl− ion. its concentration is twice that of the cl− ion. its concentration is one-third that of the cl− ion. part c a scientist wants to make a solution of tribasic sodium phosphate, na3po4, for a laboratory experiment. how many grams of na3po4 will be needed to produce 550 ml of a solution that has a concentration of na+ ions of 0.700 m ? express your answer numerically in grams. view available hint(s) mass of na3po4 n a 3 p o 4 = nothing g provide feedback

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.