【ツール】分子量と質量からモル数を計算

<script src="https://code.jquery.com/jquery-3.6.3.min.js" integrity="sha256-pvPw+upLPUjgMXY0G+8O0xUf+/Im1MZjXxxgOcBQBXU=" crossorigin="anonymous"></script>

<p><label>分子量：</label><input type="Input" id="mw" value="12">
    <select id="da">
        <option value="Da" selected>Da</option>
        <option value="kDa">kDa</option>
    </select>
</p>
<p><label>質量　：</label><input type="Input" id="weight" value="12">
    <select id="order">
        <option value="kg">kg</option>
        <option value="g" selected>g</option>
        <option value="mg">mg</option>
        <option value="ug">ug</option>
        <option value="ng">ng</option>
    </select>
</p>
<p><button id="button">計算する</button></p>
<p></p>
<p>モル数：<span id="mol">　　　　　</span> <span id="mol_order"></span>mol</p>
<script>
    $("button").on("click", function(){
        let mw = $("#mw").val();
        let da = $('#da').val();
        let weight = $("#weight").val();
        let order = $('#order').val();

        let da_order
        if(da == "kDa"){
            da_order = 1000;
        }else{
            da_order = 1;
        }
        full_mw = mw * da_order;

        let weight_order
        if(order == "kg"){
            weight_order = 1000;
        }else if(order == "g"){
            weight_order = 1;
        }else if(order == "mg"){
            weight_order = 10**(-3);
        }else if(order == "ug"){
            weight_order = 10**(-6);
        }else if(order == "ng"){
            weight_order = 10**(-9);
        }
        full_weight = weight * weight_order;

        mol = full_weight / full_mw;
        
        let mol_order = Math.floor(Math.log10(mol))

        let mol_order_str
        if(mol_order <= -12){
            mol = mol * 10**(12);
            mol_order_str = "p";
        }else if(mol_order <= -9){
            mol = mol * 10**(9);
            mol_order_str = "n";
        }else if(mol_order <= -6){
            mol = mol * 10**(6);
            mol_order_str = "u";
        }else if(mol_order <= -3){
            mol = mol * 10**(3);
            mol_order_str = "m";
        }else if(mol_order <= 0){
            mol = mol;
            mol_order_str = " ";
        }else if(mol_order <= 3){
            mol = mol * 10**(-3);
            mol_order_str = "k";
        }

        console.log(mol, mol_order_str)
        $("#mol").text(mol.toFixed(3));
        $("#mol_order").text(mol_order_str);
    })
</script>