An early model of the atom was developed in 1913 by Danish scientist Niels Bohr (1885–1962). The Bohr model shows the atom as a central nucleus containing protons and neutrons with the electrons in circular orbitals at specific distances from the nucleus . These orbits form electron shells or energy levels, which are a way of visualizing the number of electrons in the various shells. These energy levels are designated by a number and the symbol "n." For example, 1n represents the first energy level located closest to the nucleus.
Answer:
OCO
Another way of writing CO₂
Explanation:
A reaction equation has <u>reactants on the left</u> and <u>products on the right</u>.
The reactants are carbon and oxygen. The product is carbon dioxide.
C + O₂ → CO₂
You might see the equation both ways.
C + O₂ → OCO
C + O₂ in the products would mean no reaction has occurred. The problem can <u>solid carbon can burn in oxygen</u>, so a reaction will occur. For no reaction, you would put "NR" in the products.
<u>OCO is the structural way of writing CO₂.</u> Both have one carbon atom (C) and two oxygen atoms (O).
C + 2O is not possible. Oxygen, if alone, has to be at least O₂ because it's a <u>diatomic molecule</u>.
You would have to dig up 261 g of sylvanite.
Mass of sylvanite = 73.0 g Au × (100 g sylvanite/28.0 g Au) = <em>261 g</em> sylvanite.
Answer: 40.1%
Explanation: The mass of calcium in this compound is equal to 40.1 grams because there's one atom of calcium present and calcium has an atomic mass of 40.1 . The molar mass of the compound is 100.1 grams. Using the handy equation above, we get: Mass percent = 40.1 g Ca⁄100.1 g CaCO3 × 100% = 40.1% Ca.
Answer:
endothermic reaction
Explantion:
The definition for endothermic is:
describing a process that involves the absorption of energy from the surroundings by substances undergoing change.
Think of <em>en-</em>dothermic as energy entering and <em>ex-</em>othermic as energy exiting.
