8.
a student performing an investigation of chemical reactions mixes two aqueous solutions and observes
a change in color. color change is most indicative of which type of chemical reaction?
a neutralization
b precipitation
c oxidation-reduction
d acid-base

The big bang nucleosynthesis theory states that elements were produced in the first few minutes of the big bang while elements have their origins in the interiors of stars, forming much later in the history of the universe.

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.

Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.