If a piece of charcoal is taken and set on fire it will evolve CO2 and heat. Charcoal is solid but carbon dioxide is gaseous. This is an example of change of state and evolve of heat during chemical reaction.
Answer:
protons and neutrons
Explanation:
The nucleus of the atom contains protons and neutrons. The electrons of the atom orbit the nucleus.
The three parts are vacuole , cell wall , chloroplast
Answer:
Explanation:
Drug for the treatment of disease. Chemistry contributes to the preparation and use of materials for surgery (sutures, artificial skin, and sterile materials). ...
Surgical procedure. ...
Blood samples for laboratory testing. ...
Blood glucose testing device.
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
