The specific heat capacity (c) of a substance is the thermal energy required
to raise one gram of the substance by one degree celsius. the total amount
of thermal energy (q) added to a sample of a substance can be calculated
by multiplying the specific heat capacity (c) by the mass of the sample (m)
and the temperature change (t): q c m t. it takes 125 kilojoules (kj)
of energy to heat a cup of water, increasing its temperature by 1°c. what
is the temperature change in °c of the cup of water after 750 kj of energy
are used? s

Temperature of the same cup of water will rise by 6 °C unless it boils.

.

However, neither nor is given.

Adding to this cup of water of mass rises its temperature by .

In other words,

.

Both and are constant for the same cup of water unless the water boils. It's possible to reuse the value of in the second calculation. Here's how:

.

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.