<ng-container matColumnDef="{{column}}" *ngFor="let column of columnsToDisplay">
        <th mat-header-cell *matHeaderCellDef> {{column}} </th>
        <td mat-cell *matCellDef="let element"
        [class.disable]="element[column] == 'Hydrogen' || element[column] == '1.0079'
        || element[column] == 1 ||element[column] == 'H'">  {{element[column]}} </td>
</ng-container>

...
<tr mat-row *matRowDef="let element; columns: columnsToDisplay;"
  class="example-element-row"
  [class.example-expanded-row]="expandedElement === element"
  (click)="expandedElement = expandedElement === element ? null : element">
</tr>
...

...
    <!-- Weight Column -->
    <ng-container matColumnDef="weight">
        <th mat-header-cell mat-sort-header *matHeaderCellDef> Weight </th>
        <td mat-cell *matCellDef="let element" class="example-element-row" [class.example-expanded-row]="expandedElement === element"
         (click)="expandedElement = expandedElement === element ? null : element"> {{element.weight}} </td>
    </ng-container>
    ...