You have to do your chemistry homework, but you hate looking up elements on the periodic table! write a program that takes the name of an element (as a string, independent of case) from standard input and prints a double representing its atomic weight to standard output. only implement the program for the first three elements, hydrogren, helium, and lithium, which have the respective atomic weights 1.008, 4.0026, and 6.94. if anything else is given as input, print the statement "sorry, i don't recognize that element! "

// import the Scanner class to allow for standard input

import java.util.Scanner;

// Declare the class for the program

public class ChemistryHomework {

// Write the main method header

public static void main(String[] args) {

   // Create an object of the Scanner class

   // to read from the standard input

   Scanner input = new Scanner(System.in);

       // Prompt the user to enter an element    

      System.out.println("Please enter the element");

       // Receive and store the user input

       String element = input.nextLine();

       // Check if the user input is "hydrogen", "helium" or "lithium"        

       // By ignoring case, if it is "hydrogen", return a text containing the

       // atomic weight of hydrogen which is 1.008

      if (element.equalsIgnoreCase("hydrogen")){

           System.out.println("The weight of " + element + " is " + 1.008);

       }

       // Else, if by ignoring case it is "helium", return a text containing the

       // atomic weight of helium which is 4.0026

       else if(element.equalsIgnoreCase("helium")){

           System.out.println("The weight of " + element + " is " + 4.0026);

       }

       // Else, if by ignoring case it is "lithium", return a text containing the

       // atomic weight of lithium which is 6.94

       else if(element.equalsIgnoreCase("lithium")){

           System.out.println("The weight of " + element + " is " + 6.94);

       }

       // Otherwise, return an error text        

       else {

           System.out.println("Sorry, I don't recognize that element!");

       }

   }             // End of main method

}             //  End of class declaration

>> Please enter the element

helium

>> The weight of helium is 4.0026

>> Please enter the element

another

>> Sorry, I don't recognize that element!

Comments;

i. The above code has been written in Java.

ii. The code contains comments explaining every line of the code. Kindly go through the comments carefully.

iii. To ignore case of a string, the string method equalsIgnoreCase() is used as shown in the if...else statements of the code.

iv. The code without comments has been re-written as follows;

import java.util.Scanner;

public class ChemistryHomework {

   public static void main(String[] args) {

   Scanner input = new Scanner(System.in);

       System.out.println("Please enter the element");

       String element = input.nextLine();

       if (element.equalsIgnoreCase("hydrogen")){

           System.out.println("The weight of " + element + " is " + 1.008);

       }

       else if(element.equalsIgnoreCase("helium")){

           System.out.println("The weight of " + element + " is " + 4.0026);

       }

       else if(element.equalsIgnoreCase("lithium")){

           System.out.println("The weight of " + element + " is " + 6.94);

       }

       else {

           System.out.println("Sorry, I don't recognize that element!");

       }

   }

  }

answer: 2 min

explanation:

they run fast