ACT Science 2

Front

What is the pH level at which phenolphthalein undergoes a color change?

Back

Phenolphthalein undergoes a color change at a higher pH level because it reacts in more basic solutions.

Front

In a light curve, what does a deeper primary minimum indicate about the stars in a system?

Back

A deeper primary minimum indicates a more extreme difference between the magnitudes of the two stars.

Front

What happens to the light curves of a system when viewed from a line of sight that is perpendicular to the orbital plane?

Back

The light curves would indicate no difference in magnitude over time.

Front

What color change indicates the completion of a reaction in a basic solution when using bromocresol green?

Back

The addition of bromocresol green results in a blue color.

Front

How does the orbital period of a star system relate to the depth of its primary minimum?

Back

A shorter orbital period can lead to a shallower primary minimum if the stars have similar magnitudes.

Front

What is the role of indicators like bromothymol blue in acid-base reactions?

Back

Indicators change color at specific pH levels, signaling the acidity or basicity of a solution.

Front

What does a light curve represent in astrophysics?

Back

A light curve represents the brightness of a star system over time, often indicating eclipses or transits.

Front

What is the significance of the primary and secondary minima in a light curve?

Back

The primary minimum occurs when one star eclipses another, while the secondary minimum occurs when the light from the system is partially blocked.

Front

What is the relationship between the magnitude difference of stars and the observed light curve?

Back

A greater magnitude difference results in a more pronounced primary minimum in the light curve.

Front

What is the definition of pH?

Back

pH is a measure of the acidity or basicity of a solution, on a scale from 0 to 14.