Answer:
Option B is correct.
4
Explanation:
We know that an atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example, if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
In given problem we are given with 2 neutrons of helium. We know that the atomic number of He is 2. Thus Mass number of He is,
Number of neutrons + number of proton
2 + 2 = 4
Thus, option B is correct.
Answer: <em>When you take the top off of a bottle of soda, the pressure inside the bottle decreases and goes to the same pressure as the atmosphere. When that happens the carbon dioxide inside is no longer forced to be a liquid and turns back into a gas, causing the bubbles that we're so familiar with.</em>
Explanation:
However, producing foaming carbon dioxide gas by shaking a bottle of soda water is a physical change, while producing foaming carbon dioxide gas by combining baking soda and vinegar is a chemical change. ... Because no chemical bonds are broken and no new molecules are formed, this is a physical change in the system.
Answer:
Balanced reaction:
3 H2 (g) + N2 (g) → 2 NH3 (g)
Use stoichiometry to convert g of H2 to g of NH3. The process would be:
g H2 → mol H2 → mol NH3 → g NH3
12.0 g H2 x (1 mol H2 / 2.02 g H2) x (2 mol NH3 / 3 mol H2) x (17.03 g NH3 / 1 mol NH3) = 67.4 g NH3
Explanation: See above
Hope this helps, friend.
Answer:
0.0498 mol
Explanation:
Number of moles = concentration in mol/L × volume in L
Concentration = 1 M = 1 mol/L
Volume = 49.8 mL = 49.8/1000 = 0.0498 L
Number of moles = 1×0.0498 = 0.0498 mol
Option B:
Global climate is complex, so changes in global climate are hard to predict.
