S1 Final 2024

Front

What is electronegativity?

Back

Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. It is a key concept in understanding chemical bonding.

Front

Which element has the least electronegativity among Li, Na, K, and Rb?

Back

Rubidium (Rb) has the least electronegativity among these elements.

Front

How do you calculate mass using density and volume?

Back

Mass = Density × Volume. For example, if a rock has a density of 8 g/ml and a volume of 5 ml, its mass is 40 g.

Front

What is the formula to find the density of an object?

Back

Density = Mass / Volume.

Front

How many valence electrons does Oxygen (O) have?

Back

Oxygen has 6 valence electrons.

Front

What are valence electrons?

Back

Valence electrons are the electrons in the outermost shell of an atom that are involved in forming bonds.

Front

What is an isotope?

Back

An isotope is a variant of a chemical element that has the same number of protons but a different number of neutrons.

Front

What is the name of the isotope with atomic number 38 and 47 neutrons?

Back

The isotope is Strontium-85.

Front

What is significant figures in mathematics?

Back

Significant figures are the digits in a number that contribute to its precision. They include all non-zero digits, any zeros between significant digits, and trailing zeros in the decimal portion.

Front

How do you round off to one significant figure?

Back

To round off to one significant figure, look at the first non-zero digit and round based on the digit immediately following it.