A student compared some chemical and physical properties of three pure substances. Her data are recorded in the chart above. What is a logical conclusion the student can draw
about hare substances?
Pure substances have the same chemical and physical properties.
Pure substances have the same chemical properties, but different physical properties.
O Pure substances have the different chemical properties, but the same physical properties.
O Pure substances have different chemical and physical properties.

In a reaction (at equilibrium) that makes more moles of gas than it consumes, what is the effect of increasing the pressure?

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)