Как исправить ошибку при использовании SQLite в kotlin?

Сейчас я пишу программу для вычисления молекулярных масс на Kotlin, и я решил использовать SQLite, для создания БД с названиями элементов и их свойствами, но при запуске моего кода на устройстве приложение вылетало с данной ошибкой:

E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.listochek.chem.calc, PID: 3941
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.listochek.chem.calc/com.listochek.chem.calc.MainActivity}: android.database.sqlite.SQLiteException: near "AUTOINCREMENT": syntax error (code 1 SQLITE_ERROR): , while compiling: CREATE TABLE IF NOT EXISTS `Elements`(id INTEGER PRIMARY KEY UNIQUE AUTOINCREMENT, Химический элемент TEXT, Символ TEXT, Атомная масса REAL);
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2946)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3081)
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1831)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:201)
    at android.app.ActivityThread.main(ActivityThread.java:6810)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
 Caused by: android.database.sqlite.SQLiteException: near "AUTOINCREMENT": syntax error (code 1 SQLITE_ERROR): , while compiling: CREATE TABLE IF NOT EXISTS `Elements`(id INTEGER PRIMARY KEY UNIQUE AUTOINCREMENT, Химический элемент TEXT, Символ TEXT, Атомная масса REAL);
    at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
    at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:903)
    at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:514)
    at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
    at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
    at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
    at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1770)
    at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1698)
    at org.jetbrains.anko.db.DatabaseKt.createTable(Database.kt:80)
    at com.listochek.chem.calc.Data.DBHelper.onCreate(DBHelper.kt:20)
    at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:393)
    at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:298)
    at org.jetbrains.anko.db.ManagedSQLiteOpenHelper.openDatabase(Database.kt:186)
    at org.jetbrains.anko.db.ManagedSQLiteOpenHelper.use(Database.kt:177)
    at com.listochek.chem.calc.MainActivity.onCreate(MainActivity.kt:20)
    at android.app.Activity.performCreate(Activity.java:7224)
    at android.app.Activity.performCreate(Activity.java:7213)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1272)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2926)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3081) 
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1831) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:201) 
    at android.app.ActivityThread.main(ActivityThread.java:6810) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)

Код MainActivity.kt:

class MainActivity : AppCompatActivity() {

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    database.use {
        insert(Elements.TABLE_NAME,
              Elements.COLUMN_ID to 1,
               Elements.COLUMN_ELEMENT to "Водород",
               Elements.COLUMN_SYMBOL to "H",
               Elements.COLUMN_MASS to 1.00794)
        insert(Elements.TABLE_NAME,
            Elements.COLUMN_ID to 2,
            Elements.COLUMN_ELEMENT to "Гелий",
            Elements.COLUMN_SYMBOL to "He",
            Elements.COLUMN_MASS to 4.00260)
    }
    val test = database.use {
        select(Elements.TABLE_NAME).exec { parseList<Any>(classParser()) }
    }
    ListView.adapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, test)
}
}

Код model.kt:

data class Elements(var id : Int, var Element : String, var Symbol : String, var Mass : Double) {
companion object {
    const val TABLE_NAME = "Elements"
    const val COLUMN_ID = "id"
    const val COLUMN_ELEMENT = "Element"
    const val COLUMN_SYMBOL = "Symbol"
    const val COLUMN_MASS = ""
}
}

Код DBHelper.kt:

код DBHelper:

class DBHelper(ctx: Context) : ManagedSQLiteOpenHelper(ctx, "Elements", null, 1) {
companion object {
    private var instance: DBHelper? = null
    @Synchronized
    fun getInstance(ctx: Context): DBHelper {
        if (instance == null) {
            instance = DBHelper(ctx.getApplicationContext())
        }
        return instance!!
    }
}

override fun onCreate(db: SQLiteDatabase) {
    db.createTable("Elements", true,
        "id" to INTEGER + PRIMARY_KEY + UNIQUE + AUTOINCREMENT,
        "Химический элемент" to TEXT,
        "Символ" to TEXT,
        "Атомная масса" to REAL
    )
}

override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
    db.dropTable("Elements", true)
}
}

val Context.database: DBHelper get() = DBHelper.getInstance(applicationContext)

Объясните мне, в чём заключается ошибка и как её исправить