Answer:
Fe + 3NaBr → FeBr₃ + 3Na
Explanation:
Single replacement:
It is the reaction in which one elements replace the other element in compound.
AB + C → AC + B
Chemical equation:
Fe + 3NaBr → FeBr₃ + 3Na
This chemical equation shows the single replacement reaction. Iron replace the sodium and react with bromine.
All other options are incorrect because,
Ca(OH)₂ + H₂SO₄ → CaSO₄ + 2H₂O
It is double replacement reaction.
CH₄ + 2O₂ → CO₂ + 2H₂O
This reaction equation shows combustion.
H₂O + CO₂ → H₂CO₃
This is synthesis reaction.
Answer:
The value of an intensive property may vary with time and its position within the system. Examples of intensive properties include temperature, velocity, mass density, specific volume, and specific energy. An extensive property does not have a value at a point, and its value depends on the extent or size of the system.
Answer:
Evaporation and gravity cause water to move through the water cycle.
Explanation:
Evaporation turns liquid water into a gas, and brings it up into the atmosphere, where the gas condenses into frozen water molecules, which stick to each other. When a clump of water molecules gets too heavy, gravity pulls them down to the surface as precipitation. Depending on the temperature, the frozen water droplets may melt, or stay frozen.
Gravity brings precipitation to the ground.
Water has to heat up from high temperature, from either the sun or another heat source, to change the form from gas to liquid.
Water vapor must get to a certain temperature of cold to freeze, causing it to condense from a gas to liquid.
Thermal energy causes evaporation of water, which allows the water to be reprecipitated once again.
Answer: No one. All these molecules are nonpolar.
Explanation: Dipole-dipole attractions occur only between polar molecules. To know if a molecule is polar, you have to observe if their dipole moment (μ) is different from 0. You can do this by observing the vectors of charge in each molecule.
In all the molecules of the alternatives, the overall molecule is nonpolar (the sum of the vectors is equal to 0). So, these molecules are attracted only by induced dipole forces (weak forces that exist between nonpolar molecules).
For F2, this molecule is nonpolar because is composed of equal atoms. So, there isn't an atom which pulls the charge for itself.
