What is the source of energy in most ecosystems?

animals

plants

oxygen

sunlight

What is safer to drink 113 ml of HCl or 244 ml of NaOH

16. Brass is an alloy made up of A. aluminium and zinc. B. copper and tin C. copper and zinc. D. iron and carbon

What is A segment of 20 amino acids from a protein chain called

Given the equation representing a phase change at equilibrium: H2O (s) H2O (l) Which statement describes this equilibrium? (1) The H2O (s) melts faster than the H2O (l) freezes. (2) The H2O (l) freezes faster than the H2O (s) melts.

Name four components of the blood

A flask containing 155cm^3 of hydrogen was collected under a pressure of 22.5kPa. What pressure would have been required in order for the volume of the gas to have been 90.0 cm^3 at constant temperature?

Which change is most likely to occur when a molecule of H2 and a molecule of I2 collide with proper orientation and sufficient energy? 1. a chemical change, because a compound is formed 2. a chemical change, because an element is formed 3.

Which substance is a diatomic molecule? a. he b. o2 c. co2 d. h2o?

What is the difference between the electronegativity values of sodium and bromine?

Which of the following elements is the most stable element? argon, manganese, phosphorus, robidium