I have reviewed the types of reactions but am still not sure what it is.

Cs2+H2O arrow CsOH+H2
In the products, where is the H in CsOH coming from? What type of reaction is it?

In the given reaction, Cs2 + H2O → CsOH + H2, the hydrogen atom (H) in CsOH comes from the water molecule (H2O). Let me explain how you can figure this out.

To understand the reaction, we first need to know that Cs is the chemical symbol for cesium, and OH is the hydroxide ion. CsOH is the chemical formula for cesium hydroxide, which consists of a cesium ion (Cs+) and a hydroxide ion (OH-).

Now, let's break down the reaction step by step:

Cs2 + H2O → CsOH + H2

1. The reactants are cesium (Cs) and water (H2O).

2. Cesium (Cs) is an alkali metal with a valence of +1, which means it readily gives up one electron to form a positive ion Cs+.

3. Water (H2O) is a polar molecule consisting of two hydrogen atoms (H) and one oxygen atom (O). In a water molecule, the oxygen atom is more electronegative than hydrogen atoms, resulting in a partial negative charge on the oxygen atom and partial positive charges on the hydrogen atoms.

4. In the reaction, the cesium atoms (Cs) react with water (H2O) to form cesium hydroxide (CsOH) and hydrogen gas (H2). The Cs atoms in Cs2 lose electrons to form Cs+ ions.

5. The Cs+ ions combine with hydroxide (OH-) ions produced by the dissociation of water to form CsOH. The OH- ions come from the water molecules, where one water molecule donates a hydroxide (OH-) ion.

6. The remaining hydrogen atoms (H) from the water molecules combine to form molecular hydrogen (H2).

Now, to answer your second question, this type of reaction is called a displacement reaction or a single displacement reaction. It occurs when an element reacts with a compound, displacing another element in the compound and forming a new compound.

In this case, cesium (Cs) displaces hydrogen (H) from water (H2O) to form cesium hydroxide (CsOH) and hydrogen gas (H2).