Why does every human measurement have uncertainty associated with it? Why must we manage the uncertainty during calculations?

In a chemical cold pack, two substances are kept separate by a divider. when the divider is broken, the substances mix and absorb heat from the surroundings. the chemical cold pack feels cold.

An element belongs to group 9. what common name might be used to describe the group to which this element belongs?

Why doesn't the reaction Pb+Zn (C2H3O2) 2--> Zn + Pb (C2H3O2) 2 occur?

A neutron star is a compact star that forms from the gravitational collapse of a very massive star. The inward gravitational force can be so strong that a neutron star that started out to be twice as large as our Sun might have a radius of 13 km

What is one major difference between volcanic activity on Earth and volcanic activity on Mars, Venus, and the moon? Explain.

When the moon is farthest from the sun and viewed from earth, the moon appears to be a ... ?

How much uranium was used in the first atomic bomb?

How many grams of chromium are required to react with 125ml of 0.75m cuso4?

Of the following, which does NOT have bilateral symmetry? a. Humans b. Frogs c. Fish d. Jellyfish

What is pure chemistry and applied chemistry?