TEKS: Chapter 112. Science See All Teacher Resources

112.20.b.5

 (5) Matter and energy. The student knows that matter is composed of atoms and has chemical and physical properties. The student is expected to:

• (A) describe the structure of atoms, including the masses, electrical charges, and locations, of protons and neutrons in the nucleus and electrons in the electron cloud; 
• (B) identify that protons determine an element's identity and valence electrons determine its chemical properties, including reactivity; 
• (C) interpret the arrangement of the Periodic Table, including groups and periods, to explain how properties are used to classify elements; 
• (D) recognize that chemical formulas are used to identify substances and determine the number of atoms of each element in chemical formulas containing subscripts; and
• (E) investigate how evidence of chemical reactions indicate that new substances with different properties are formed and how that relates to the law of conservation of mass.