Boron

Boron react hydrochloric acid, HCl, hydrofluoric acid, HF, forming the halides BCl₃ and BF₃ [11].

2 B(s) + 6 HCl(g) 2 BCl₃(l) + 3 H₂(g)
2 B(s) + 6 HF(g) 2 BF₃(g) + 3 H₂(g)


Boron reacts with nitric and sulfuric acid, when heated, both forming boric acid (B(OH)₃ or H₃BO₃) [12]:

B(s) + 3 HNO₃(aq) B(OH)₃(aq) + 3 NO₂(g)
2 B(s) + 3 H₂SO₄(aq) 2 B(OH)₃(aq) + 3 SO₂(g)

Boron does not react with air at room temperature. At 700 °C, boron burns/reacts with oxygen, forming boron(III)oxide, B₂O₃ [6].

4 B(s) + 3 O₂(g) 2 B₂O₃(s)


Heating boron with nitrogen brings the formation of boron nitride (BN) [6]:

2 B(s) + N₂(g) 2 BN(s)

Boron reacts directly with carbon in an electric arc, forming boron carbide, B₄C [6].

4 B(s) + C(s) B₄C(s)

Boron reacts with the halogens fluorine, chlorine and bromine, forming the respective boron(III)trihalides. For iodine this reaction does not occur [6].

2 B(s) + 3 F₂(g) 2 BF₃(g)
2 B(s) + 3 Cl₂(g) 2 BCl₃(l)
2 B(s) + 3 Br₂(g) 2 BBr₃(l)

Boron reacts directly with sulfur at elevated temperature, forming boron(III)sulfide, B₂S₃ [6].

2 B(s) + 3 S(s) 2 B₂S₃(s)

Boron does not react with water under normal conditions, due to the surface being passivated by oxygen [9].

At temperatures above 100 °C, boron reacts with water, forming boric acid [10]. The formation is a two-step process [9]:

3 H₂O(g) + 2 B(s) 2 B₂O₃(l) + 3 H₂(g)
3 H₂O(g) + B₂O₃(l) 2 H₃BO₃(g)

Method 4500-B D Inductively Coupled Plasma Method [1]. A portion of the sample is digested in a combination of acids. The digest is aspirated into an 8,000 K argon plasma where resulting light emission is quantified for 30 elements simultaneously.

Method limit of detection in water = 0.05 mg/L
Method limit of detection in soil = 1.00 mg/kg