摩尔质量/分子量

复制from pyparsing import Word, nums, Optional, Group, ZeroOrMore, ParseException
import chemparse

# 直接解析化学式字符串
formula = "H2SO4"
parsed = chemparse.parse_formula(formula)
print(parsed)  # {'H': 2.0, 'S': 1.0, 'O': 4.0}

# 计算相对分子质量（使用内置原子量）
mass = chemparse.calculate_mass(formula)
print(f"{formula} 相对分子质量: {mass:.4f} g/mol")  # H2SO4 相对分子质量: 98.0785 g/mol

# 处理含括号的复杂式
complex_formula = "Ca(OH)2"
mass = chemparse.calculate_mass(complex_formula)
print(f"{complex_formula} 相对分子质量: {mass:.4f} g/mol")  # Ca(OH)2 相对分子质量: 74.0927 g/mol

复制package main

import (
	"fmt"
	"regexp"
	"strconv"
	"strings"
)

// 简化的原子量表（仅示例，完整版需引入外部数据）
var atomicMasses = map[string]float64{
	"H": 1.008, "He": 4.0026, "C": 12.011, "N": 14.007,
	"O": 15.999, "F": 18.998, "Na": 22.990, "S": 32.065,
	"Cl": 35.45, "Ca": 40.078, "Fe": 55.845, "Cu": 63.546,
}

func parseFormula(formula string) (map[string]float64, error) {
	re := regexp.MustCompile(`([A-Z][a-z]?)(\d*)`)
	matches := re.FindAllStringSubmatch(formula, -1)
	result := make(map[string]float64)
	for _, m := range matches {
		elem := m[1]
		count := 1.0
		if m[2] != "" {
			c, err := strconv.ParseFloat(m[2], 64)
			if err != nil {
				return nil, fmt.Errorf("invalid count: %s", m[2])
			}
			count = c
		}
		result[elem] += count
	}
	return result, nil
}

func main() {
	formula := "H2SO4"
	elements, err := parseFormula(formula)
	if err != nil {
		fmt.Println("Error:", err)
		return
	}
	var mass float64
	for elem, count := range elements {
		if am, ok := atomicMasses[elem]; ok {
			mass += am * count
		} else {
			fmt.Printf("Warning: unknown element %s\n", elem)
		}
	}
	fmt.Printf("%s 相对分子质量: %.4f g/mol\n", formula, mass) // H2SO4 相对分子质量: 98.0780 g/mol
}

复制// 使用 chem-js 库（npm install chem-js）
const { parseFormula, calculateMass } = require('chem-js');

// 解析化学式
const formula = 'H2SO4';
const parsed = parseFormula(formula);
console.log(parsed); // { H: 2, S: 1, O: 4 }

// 计算相对分子质量
const mass = calculateMass(formula);
console.log(`${formula} 相对分子质量: ${mass.toFixed(4)} g/mol`); // H2SO4 相对分子质量: 98.0785 g/mol

// 处理带括号的复杂式
const complex = 'Fe2(SO4)3';
const complexMass = calculateMass(complex);
console.log(`${complex} 相对分子质量: ${complexMass.toFixed(4)} g/mol`); // Fe2(SO4)3 相对分子质量: 399.8778 g/mol