chem.py

Created by laigna
Created on March 14, 2026
7.62 KB
Chemistry solver with molar mass calculator, moles/mass conversions, gas volume at STP, solution dilution (C1V1=C2V2), pH calculator, mass percentage, and element table.
# Chem Solver - NumWorks
# Created by Alvar Laigna - https://alvarlaigna.com
# Arrows:select OK:choose Back:back
from kandinsky import fill_rect as F,draw_string as D
from ion import keydown as K
from time import sleep as Z
from math import log
SW,SH=320,222
BK=(0,)*3;WH=(255,)*3
BL=(50,110,230);TL=(0,190,190)
YL=(220,200,60);DG=(120,)*3

okv=1 if K(4)or K(52) else 0

def okd():
 return K(4)or K(52)

def okp():
 global okv
 d=okd()
 if d and not okv:
  okv=1
  return True
 if not d:okv=0
 return False

def wup():
 while okd():Z(0.02)
 Z(0.12)

EL={"H":1.008,"He":4.003,"Li":6.941,"Be":9.012,
"B":10.81,"C":12.011,"N":14.007,"O":15.999,
"F":18.998,"Ne":20.18,"Na":22.99,"Mg":24.305,
"Al":26.982,"Si":28.086,"P":30.974,"S":32.065,
"Cl":35.453,"Ar":39.948,"K":39.098,"Ca":40.078,
"Ti":47.867,"Cr":51.996,"Mn":54.938,"Fe":55.845,
"Co":58.933,"Ni":58.693,"Cu":63.546,"Zn":65.38,
"Br":79.904,"Ag":107.87,"Sn":118.71,"I":126.9,
"Ba":137.33,"Au":196.97,"Hg":200.59,"Pb":207.2}

def menu(title,items,sub=False):
 sel=0;n=len(items)
 while True:
  F(0,0,SW,SH,BK)
  D(title,SW//2-len(title)*5,6,TL,BK)
  F(0,24,SW,2,(40,)*3)
  for i in range(n):
   y=34+i*22
   if i==sel:
    F(8,y,SW-16,20,BL)
    D("> "+items[i],14,y+2,WH,BL)
   else:
    D("  "+items[i],14,y+2,DG,BK)
  if sub:D("Back=return",100,SH-16,(60,)*3,BK)
  else:D("Back=quit",115,SH-16,(60,)*3,BK)
  while True:
   if K(1):sel=(sel-1)%n;Z(0.15);break
   if K(2):sel=(sel+1)%n;Z(0.15);break
   if okp():wup();return sel
   if K(17):return-1
   Z(0.04)

def inp(prompt):
 try:return float(input(prompt))
 except:return None

def inps(prompt):
 return input(prompt).strip()

def show(lines):
 F(0,0,SW,SH,BK)
 D("RESULT",130,6,TL,BK)
 F(0,24,SW,2,(40,)*3)
 for i,ln in enumerate(lines):
  c=YL if i==len(lines)-1 else WH
  D(str(ln),14,34+i*20,c,BK)
 D("OK=back",130,SH-16,DG,BK)
 while True:
  if okp()or K(17):wup();return
  Z(0.04)

def parse(fm):
 el={};i=0
 while i<len(fm):
  if fm[i].isupper():
   s=fm[i];i+=1
   while i<len(fm) and fm[i].islower():
    s+=fm[i];i+=1
   n=""
   while i<len(fm) and fm[i].isdigit():
    n+=fm[i];i+=1
   n=int(n) if n else 1
   el[s]=el.get(s,0)+n
  else:i+=1
 return el

def molar(fm):
 el=parse(fm);m=0
 for s,n in el.items():
  if s not in EL:return None,s
  m+=EL[s]*n
 return m,None

def f_molar():
 fm=inps("Formula (eg H2O): ")
 if fm:
  m,err=molar(fm)
  if err:show(["Unknown element: "+err])
  elif m:
   el=parse(fm)
   r=["Formula: "+fm]
   for s,n in el.items():
    r+=[s+": "+str(n)+"x"+str(EL[s])+"="+str(round(EL[s]*n,3))]
   r+=["M = "+str(round(m,4))+" g/mol"]
   show(r)

def f_moles():
 c=menu("Moles / Mass",
  ["n = m / M  (find moles)",
   "m = n x M  (find mass)",
   "M = m / n  (find molar mass)"],True)
 if c==0:
  m=inp("Mass m (g): ");mm=inp("Molar mass M (g/mol): ")
  if m is not None and mm and mm!=0:
   show(["n = m / M",
    "m="+str(m)+"g  M="+str(mm)+"g/mol",
    "n = "+str(round(m/mm,6))+" mol"])
 elif c==1:
  n=inp("Moles n (mol): ");mm=inp("Molar mass M (g/mol): ")
  if n is not None and mm is not None:
   show(["m = n x M",
    "n="+str(n)+"mol  M="+str(mm)+"g/mol",
    "m = "+str(round(n*mm,6))+" g"])
 elif c==2:
  m=inp("Mass m (g): ");n=inp("Moles n (mol): ")
  if m is not None and n and n!=0:
   show(["M = m / n",
    "m="+str(m)+"g  n="+str(n)+"mol",
    "M = "+str(round(m/n,4))+" g/mol"])

def f_gas():
 c=menu("Gas at STP (22.4 L/mol)",
  ["V = n x Vm  (find volume)",
   "n = V / Vm  (find moles)",
   "From mass (enter M)"],True)
 if c==0:
  n=inp("Moles n (mol): ")
  if n is not None:
   show(["V = n x Vm (STP)",
    "n="+str(n)+" mol  Vm=22.4 L/mol",
    "V = "+str(round(n*22.4,4))+" L"])
 elif c==1:
  v=inp("Volume V (L): ")
  if v is not None:
   show(["n = V / Vm (STP)",
    "V="+str(v)+" L  Vm=22.4 L/mol",
    "n = "+str(round(v/22.4,6))+" mol"])
 elif c==2:
  m=inp("Mass m (g): ");mm=inp("Molar mass M (g/mol): ")
  if m is not None and mm and mm!=0:
   n=m/mm;v=n*22.4
   show(["Gas from mass (STP)",
    "m="+str(m)+"g  M="+str(mm)+"g/mol",
    "n = "+str(round(n,6))+" mol",
    "V = "+str(round(v,4))+" L"])

def f_dilute():
 c=menu("Dilution C1V1=C2V2",
  ["Find C2 (final conc)",
   "Find V2 (final volume)",
   "Find C1 (initial conc)",
   "Find V1 (initial volume)"],True)
 if c==0:
  c1=inp("C1 (mol/L): ");v1=inp("V1 (L): ")
  v2=inp("V2 (L): ")
  if c1 is not None and v1 is not None and v2 and v2!=0:
   show(["C2 = C1*V1/V2",
    "C1="+str(c1)+" V1="+str(v1)+" V2="+str(v2),
    "C2 = "+str(round(c1*v1/v2,6))+" mol/L"])
 elif c==1:
  c1=inp("C1 (mol/L): ");v1=inp("V1 (L): ")
  c2=inp("C2 (mol/L): ")
  if c1 is not None and v1 is not None and c2 and c2!=0:
   show(["V2 = C1*V1/C2",
    "C1="+str(c1)+" V1="+str(v1)+" C2="+str(c2),
    "V2 = "+str(round(c1*v1/c2,6))+" L"])
 elif c==2:
  v1=inp("V1 (L): ");c2=inp("C2 (mol/L): ")
  v2=inp("V2 (L): ")
  if v1 and v1!=0 and c2 is not None and v2 is not None:
   show(["C1 = C2*V2/V1",
    "V1="+str(v1)+" C2="+str(c2)+" V2="+str(v2),
    "C1 = "+str(round(c2*v2/v1,6))+" mol/L"])
 elif c==3:
  c1=inp("C1 (mol/L): ");c2=inp("C2 (mol/L): ")
  v2=inp("V2 (L): ")
  if c1 and c1!=0 and c2 is not None and v2 is not None:
   show(["V1 = C2*V2/C1",
    "C1="+str(c1)+" C2="+str(c2)+" V2="+str(v2),
    "V1 = "+str(round(c2*v2/c1,6))+" L"])

def f_ph():
 c=menu("pH Calculator",
  ["pH from [H+]",
   "[H+] from pH",
   "pOH from pH",
   "pH from pOH"],True)
 if c==0:
  h=inp("[H+] (mol/L): ")
  if h and h>0:
   ph=-log(h)/log(10)
   show(["pH = -log10[H+]",
    "[H+] = "+str(h)+" mol/L",
    "pH = "+str(round(ph,4)),
    "pOH = "+str(round(14-ph,4))])
 elif c==1:
  ph=inp("pH: ")
  if ph is not None:
   h=10**(-ph)
   show(["[H+] = 10^(-pH)",
    "pH = "+str(ph),
    "[H+] = "+str(h)+" mol/L",
    "pOH = "+str(round(14-ph,4))])
 elif c==2:
  ph=inp("pH: ")
  if ph is not None:
   show(["pOH = 14 - pH",
    "pH = "+str(ph),
    "pOH = "+str(round(14-ph,4))])
 elif c==3:
  poh=inp("pOH: ")
  if poh is not None:
   show(["pH = 14 - pOH",
    "pOH = "+str(poh),
    "pH = "+str(round(14-poh,4))])

def f_masspct():
 c=menu("Mass Percentage",
  ["w% (find percentage)",
   "Find solute mass",
   "Find solution mass"],True)
 if c==0:
  ms=inp("Solute mass (g): ");mt=inp("Solution mass (g): ")
  if ms is not None and mt and mt!=0:
   show(["w% = m_solute/m_solution x100",
    "m_solute="+str(ms)+"g",
    "m_solution="+str(mt)+"g",
    "w = "+str(round(ms/mt*100,4))+" %"])
 elif c==1:
  w=inp("Mass % (w%): ");mt=inp("Solution mass (g): ")
  if w is not None and mt is not None:
   show(["m_solute = w%/100 x m_solution",
    "w="+str(w)+"%  m_sol="+str(mt)+"g",
    "m_solute = "+str(round(w/100*mt,4))+" g"])
 elif c==2:
  ms=inp("Solute mass (g): ");w=inp("Mass % (w%): ")
  if ms is not None and w and w!=0:
   show(["m_solution = m_solute/(w%/100)",
    "m_solute="+str(ms)+"g  w="+str(w)+"%",
    "m_solution = "+str(round(ms/(w/100),4))+" g"])

def f_elem():
 keys=sorted(EL.keys())
 sel=0;n=len(keys);vis=7
 while True:
  F(0,0,SW,SH,BK)
  t="Elements ("+str(n)+")"
  D(t,SW//2-len(t)*5,6,TL,BK)
  F(0,24,SW,2,(40,)*3)
  top=max(0,min(sel-vis//2,n-vis))
  for i in range(vis):
   idx=top+i
   if idx>=n:break
   y=34+i*22
   s=keys[idx]
   txt=s+" - "+str(EL[s])+" g/mol"
   if idx==sel:
    F(8,y,SW-16,20,BL)
    D("> "+txt,14,y+2,WH,BL)
   else:
    D("  "+txt,14,y+2,DG,BK)
  D("Back=return",100,SH-16,(60,)*3,BK)
  while True:
   if K(1):sel=(sel-1)%n;Z(0.15);break
   if K(2):sel=(sel+1)%n;Z(0.15);break
   if K(17):return
   Z(0.04)

CATS=["Molar Mass Calculator",
 "Moles / Mass / M",
 "Gas Volume (STP)",
 "Dilution (C1V1=C2V2)",
 "pH Calculator",
 "Mass Percentage",
 "Element Table"]
FNS=[f_molar,f_moles,f_gas,f_dilute,
 f_ph,f_masspct,f_elem]
def run():
 while True:
  c=menu("Chem Solver",CATS)
  if c<0:return
  FNS[c]()
run()
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