A soda can is made from aluminum metal. To determine how many atoms of this element is present in a certain mass of the can, we need to convert the mass into units of moles by using the atomic mass of aluminum which is 26.98 g per mol. Then, we use the Avogadro's number. It represents the number of units in one mole of any substance. This has the value of 6.022 x 10^23 units / mole. This number can be used to convert the number of atoms or molecules into number of moles or vice versa.
moles Al = 15.1 g Al ( 1 mol / 26.98 g ) = 0.56 mol Al
atoms Al = 0.56 mol Al ( 6.022x10^23 atoms / 1 mol ) = 3.32x10^23 atoms
OPTION A would be the closest.
Answer:
It can lead to multiple health hazords like harmful substances and it has a huge waste of rocks and vegatation.
Explanation:
Across the world, mining contributes to erosion, sinkholes, deforestation, loss of biodiversity, significant use of water resources, dammed rivers and ponded waters, wastewater disposal issues, acid mine drainage and contamination of soil, ground and surface water, all of which can lead to health issues in local areas. Some mining methods may have significant environmental and public-health effects.
Answer:
Starting molecules not completely and quickly convert to its possible product because an activation energy barrier exist that must be overcome for conversion to product.
Explanation:
The activation energy of a chemical reaction is closely related to its rate. This is because molecules can only complete the reaction once they have reached the top of the activation energy barrier. The higher the barrier is, the fewer molecules that will have enough energy to make it over at any given moment.
Many reactions have such high activation energies that they basically don't proceed at all without an input of energy. For instance, the combustion of a fuel like propane releases energy, but the rate of reaction is effectively zero at room temperature. Once a spark has provided enough energy to get some molecules over the activation energy barrier, those molecules complete the reaction, releasing energy. The released energy helps other fuel molecules get over the energy barrier as well, leading to a chain reaction.
it must be the policy of the United States to support free people who are resisting attempted subjugation by armed minorities or by outside pressures.
