A 55.0 grams sample of strontium arsenite is mixed with 65.0 grams of chromic acid in a double replacement reaction form strontium chromate and arsenous acid. After the reaction
was performed, 45.7 g of the actual strontium chromate were collected.

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)