Answer: Oxygen usually forms two covalent bonds or a covalent double bond.
Explanation:
A covalent bond is formed by the sharing of 2 electrons, 1 electron from each of the atoms sharing their electrons.
The number of bonds that each element can form depends on the number of valence (outermost) electrons it contains. Oxygen has 6 electrons in its valence shell and needs 2 more electrons thereby forming a double bond.
Helium is a chemical element of the atomic number 2, an inert gas that is the lightest member of the noble gas series.
These means, Helium is lighter than air, and for this is why all other balloons may not float.
The helium balloon displaces an amount of air (Just like an empty water bottle displaces an amount of water). As long as the weight of the helium plus the balloon fabric is lighter than the air displaces, the balloon will float in the air.
The appropriate answer is they decrease the potential energy difference between reactant and product. They do this by bringing products and reactants together at the active site on the enzyme molecule. Enzymes are biological catalysts. They increase the rate of a chemical reaction without being used up in the reaction itself. So one molecule of an enzyme is used many times to catalyze the reaction of other molecules.
Answer:
818.2 g.
Explanation:
- Molarity is the no. of moles of solute per 1.0 L of the solution.
<em>M = (no. of moles of NaCl)/(Volume of the solution (L))</em>
<em></em>
M = 2.0 M.
no. of moles of NaCl = ??? mol,
Volume of the solution = 7.0 L.
∴ (2.0 M) = (no. of moles of NaCl)/(7.0 L)
∴ (no. of moles of NaCl) = (2.0 M)*(7.0 L) = 14.0 mol.
- To find the mass of NaCl, we can use the relation:
<em>no. of moles of NaCl = mass/molar mass</em>
<em></em>
<em>∴ mass of NaCl = (no. of moles of NaCl)*(molar mass) =</em> (14.0 mol)*(58.44 g/mol) = <em>818.2 g.</em>
Answer:
A. 2.45 L - Answer my answers is right.
