Depending on your specific school curriculum, you may be looking for one of these widely used titles:
: They offer specialized collections of control and independent work (e.g., by E. A. Segen or O. I. Sechko) specifically designed for the 7th-grade level. You can check for official digital copies on the Aversev Website . Common Topics Covered skachat sbornik zadach po khimii 7 klass
: A standard problem book used in Belarusian schools. You can find digital versions or previews on platforms like Scribd . Depending on your specific school curriculum, you may
: Calculating mass fractions of elements in a compound. Depending on your specific school curriculum