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:
Calcium would displace barium.
Explanation:
Ba(NO₃)₂ + Ca --> Ca(NO₃)₂ + Ba
There are two types of compounds: molecular/covalent and ionic.
Molecular/covalent compounds are non-metal + non-metal.
Ionic compounds are metal + non-metal.
Looking at the periodic table, barium is a metal. Calcium is also a metal.
Checking a polyatomic ions chart would tell you NO₃⁻ is a non-metal because it has a negative charge.
Since there is no metal + metal compound, the calcium metal would displace barium. The compound remains ionic.
Answer:4
Explanation:
As shown in the image attached, a face-centred cubic structure has 8 atoms at the corners and 6 face center atoms.
Each corner atom contributes to eight cell, so per unit cell 1/8 ×8 =1atom
Face center atoms contributes to two unit cells 1/2 × 6=3atoms
Total atoms =3+1=4atoms
Therefore the atoms in Al FCC per unit cell is 4
The answer is B. This is because Sodium has 1 valence electron and Fluorine has 7 valence electrons. All elements want 8 valence electrons so they may be stale, like the noble gases are. Hope this helps.
Adding hot cocoa to hot water would be a chemical change
