Answer:
Explanation:
To convert from atoms to moles, we must Avogadro's number:
This number tells us the amount of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, it is atoms of magnesium in 1 mole.
- 6.022 *10²³ atoms Mg / 1 mol mg
Now, let's set up an expression using:
Multiply this by the given number of atoms.
Flip the fraction so the atoms of magnesium can cancel.
Multiply and condense this into 1 fraction.
The original measurement had 3 significant figures, so our answer must have that many as well. For the number we calculated, that is the tenth place. The 6 in the hundredth place tells us to round the 1 to a 2.
It is about <u>92.2 moles of magnesium.</u>
Answer:
D
Explanation:
Because speed is a scalar quantity which he has only magnitude and no direction while velocity is a vector quantity because it has both magnitude and direction.
Observation is acknowledging and noting some facts from the surroundings or the environment. Usually, observation is done using the five senses of human such as the sense of sight, sense of smell, sense of touch, sense of hearing and sense of tasting. It can also be qualitative and quantitative. Qualitative observations are those who use non-numeric forms in expressing the observation however quantitative uses numeric forms in presenting the observation. Inference on the other hand is the probable explanation or interpretation based on the observation given. Therefore, the statement "The container is filled to the 350 ml mark with water " is an observation.
Answer:
-176.0 kJ/mol
Explanation:
Let's consider the following balanced reaction.
NH₃(g) + HCl(g) → NH₄Cl(s)
We can calculate the standard enthalpy change for the reaction (ΔH°rxn) using the following expression.
ΔH°rxn = 1 mol × ΔH°f(NH₄Cl(s)) - 1 mol × ΔH°f(NH₃(g)) - 1 mol × ΔH°f(HCl(g))
ΔH°rxn = 1 mol × (-314.4 kJ/mol) - 1 mol × (-46.1 kJ/mol) - 1 mol × (-92.3 kJ/mol)
ΔH°rxn = -176.0 kJ/mol
Answer: Yes, the mass will remain conserved during a physical change.
Explanation: Law of conservation of mass states that mass can neither be created nor be destroyed, but it can only be transformed from one form to another form. In a reaction, total mass on the reactant side will always be equal to the total mass on the product side.
