calculator.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>First Law of Thermodynamics Calculator</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            margin: 50px;
            background-image: url(/chem.jpg);
            background-repeat:repeat-y;
            background-size: cover;
        }

        h1 {
            text-align: center;
        }

        .container {
            max-width: 600px;
            margin: 0 auto;
            padding: 40px;
            background-color: #fff;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
        }

        label {
            display: block;
            margin-top: 15px;
            font-weight: bold;
        }

        input[type="number"] {
            width: 100%;
            padding: 10px;
            margin-top: 5px;
            border: 1px solid #ccc;
            border-radius: 5px;
        }

        button {
            margin-top: 20px;
            padding: 10px 20px;
            background-color: #28a745;
            color: #fff;
            border: none;
            border-radius: 5px;
            cursor: pointer;
        }

        button:hover {
            background-color: #218838;
        }

        .result {
            margin-top: 20px;
            font-weight: bold;
        }
    </style>
</head>

<body>

    <div class="container">
        <h1>First Law of Thermodynamics Calculator</h1>

        <label for="heat">Heat added to the system (Q in joules)</label>
        <input type="number" id="heat" placeholder="Enter heat in joules">

        <label for="work">Work done by the system (W in joules)</label>
        <input type="number" id="work" placeholder="Enter work in joules">

        <button onclick="calculate()">Calculate</button>

        <div class="result" id="result"></div>
    </div>

    <script>
        function calculate() {
            const heat = parseFloat(document.getElementById("heat").value);
            const work = parseFloat(document.getElementById("work").value);

            if (isNaN(heat) || isNaN(work)) {
                document.getElementById("result").innerText = "Please enter valid values for both heat and work.";
                return;
            }

            const internalEnergyChange = heat - work;
            document.getElementById("result").innerText = `The change in internal energy (ΔU) is: ${internalEnergyChange} J`;
        }
    </script>

</body>

</html>