Answer:
Letter B.
Explanation:
Changing its direction and climbing a steep incline can't be proven only by the graph info. You can see that it's speed isn't constant in the graph.
We have letter B left.
substance is matter of particular or definite chemical constitution ex: iron, methane
mixture are two or more substances that have been combined to retain their individual chemical characteristics ex: salt water, cola
Heat energy is required.
In distillation, the solution is first heated, where heat energy is required, such as using a bunsen burner.
When the solution is heated, the water may reach its boiling point and evaporate. However, salt does not. When water molecules evaporates, it travels through a condenser that cools it down into liquid again. Therefore we get pure water. Salt is also obtained in the original beaker.
Therefore to first start this process, heat energy is required.
Answer:
d. Sum of product enthalpies minus the sum of reactant enthalpies
Explanation:
The standard enthalpy change of a reaction (ΔH°rxn) can be calculated using the following expression:
ΔH°rxn = ∑n(products) × ΔH°f(products) - ∑n(reactants) × ΔH°f(reactants)
where,
ni are the moles of products and reactants
ΔH°f(i) are the standard enthalpies of formation of products and reactants
The magnetic fields are the reason why magnets repel and attract. eachother.