A student wants to examine a substance without changing its identity. Which of the following properties should the student examine?

A. Ductility, because it can be observed by altering the shape of the substance  

Explanation:

Changing the shape of a substance does not change its identity.

answer: e.   sour taste

explanation: acids are those substances which dissociates in water to give ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. acids are sour in taste. example: hcl

bases are those substances which dissociates in water to give ions or accepts ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. bases are bitter in taste. bases are slippery in nature.