Equation: 2K + S --> K2S
Chemical formula: K2S
<span>Molecular compounds, which are represented by molecules, are usually made of non-metals only (or of metalloids and non-metals). Ionic compounds, which are represented by formula units, are made of metals and non-metals.
More detail if you're interested: Molecules and formula units are the representative particles for molecular and ionic compounds, respectively. By that I mean, one unit of a molecular compound is a molecule...a bundle of atoms covalently bonded that exists separately from all the other molecules. One unit of an ionic compound is a formula unit. A formula unit is a representation of the compound's formula. For example, the formula unit of NaCl is one Na^+1 ion and one Cl^-1 ion. The formula unit of AlCl3 is one Al^+3 ion and three Cl^-1 ions. Ionic compounds don't have separate bundles of atoms like molecular compounds do, so the formula unit is just the smallest number of ions that it takes to represent the formula. </span>
Answer:
A Horizon - The layer called topsoil; it is found below the O horizon and above the E horizon. Seeds germinate and plant roots grow in this dark-colored layer. It is made up of humus (decomposed organic matter) mixed with mineral particles.
Answer: 2 C2H4 + 6 O2 => 4 CO2 + 4 H2O
Explanation:The coefficient are as follows: 2: 6: 4: 4
Each atom on the reactant and product side are equal.
Reactant Product
C 2x2 = 4 4x1 = 4
H 2x4 = 8 4x2 = 8
O 6x2 = 12 (4x2) + 4 = 12
Answer:
C. Energy is absorbed and released during chemical reactions,
Explanation:
All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. Endothermic reactions absorb energy, and exothermic reactions release energy.