D) warm and wet.
Water can be a catalyst, and heat speeds up reactions.
Answer:
Retrograde Motion
Explanation:
Geocentric model of planets was proposed by Ptolemy. It stated that all sun, planets and stars revolve round the earth in circular orbits.
NOTE: Ptolemy: an ancient astronomer, geographer, and mathematician who considered the Earth the center of the universe (the "Ptolemaic system").
Answer:
Pure substance B) Consists of a single element or type of compound.
Homogeneous A) Mixture that has its different components mixed evenly within the substance.
Heterogeneous D) Mixture that has its different components mixed unevenly within the substance.
Solution C) Liquid homogeneous mixture in which the solute is distributed evenly within the solvent.
Explanation:
Pure substances are a form of matter with definite constant composition and distinct properties. They consist of a single element or type of compound, as can be seen in its formula. Na, O₂, NaCl and H₂O are examples of pure substances.
When 2 or more pure substances are mixed together they form a mixture. If the mixture has its different components mixed <u>evenly</u> within the substance it is a homogeneous mixture. Whereas if the mixture has its different components mixed <u>unevenly</u> within the substance it is a heterogeneous mixture. The different parts observable in a heterogeneous mixture are known as phases.
In liquid homogeneous mixtures, we can recognize one or more substances that are in lower proportions (solutes) and one substance that is in greater proportion (solvent). This kind of mixture is known as a solution.
2H₂₍g₎ + O₂ ₍g₎→ 2H₂O
138 mol H₂ × (2 mol H₂O ÷ 2 mol H₂)= 138 mol H₂O
64 mol O₂ × (2 mol H₂O ÷ 1 mol O₂)= 128 mol H₂O
128 mol H₂O
