bkchem: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/bkchem - from package: bkchem

You may install the required package with command apt-get install {package}

Error in other languages:
bkchem: bevel nie gevind nie
bkchem: comandă negăsită
bkchem: comando não encontrado
bkchem: commande introuvable
bkchem: command not found
bkchem: käsku ei ole
bkchem: không tìm thấy lệnh
bkchem: komanda nerasta
bkchem: Kommando nicht gefunden.
bkchem: kommandot finns inte
bkchem: komut yok
bkchem: nie znaleziono polecenia
bkchem: níor aimsíodh an t-ordú
bkchem: no se encontró la orden
bkchem: no s'ha trobat l'ordre
bkchem: opdracht niet gevonden
bkchem: parancs nem található
bkchem: perintah tidak ditemukan
bkchem: príkaz nenájdený
bkchem: příkaz nenalezen
bkchem: команда не найдена
bkchem: командата не е открита
bkchem: 命令找不到
bkchem: コマンドが見つかりません