Answer:
669.48 kJ
Explanation:
According to the question, we are required to determine the heat change involved.
We know that, heat change is given by the formula;
Heat change = Mass × change in temperature × Specific heat
In this case;
Change in temperature = Final temp - initial temp
= 99.7°C - 20°C
= 79.7° C
Mass of water is 2000 g ( 2000 mL × 1 g/mL)
Specific heat of water is 4.2 J/g°C
Therefore;
Heat change = 2000 g × 79.7 °C × 4.2 J/g°C
= 669,480 joules
But, 1 kJ = 1000 J
Therefore, heat change is 669.48 kJ
c is the answer a benzene
Explanation:
Specific heat capacity is how much is required to heat the unit of mass by one degree. Therefore, if you have a higher heat capacity it required more energy, therefore, it takes longer to heat up. whereas having a lower heat capacity it takes less time to best up as it requires less energy.
The melting points of sugar and salt are above 20°C.
<h3>What is melting point?</h3>
The melting points of substances refer to the temperature at which solid substances gain enough energy to become liquids.
The room temperature is approximately 20°C. At this temperature, sugar and salt are solids. This means that the melting temperature of both substances is above 20°C.
More specifically, sugar will melt around 180 °C while salt will melt at a temperature slightly above 800 °C.
More on melting points can be found here: brainly.com/question/25777663
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C. PH3 represents a compound commonly known as phosphine, whose IUPAC name is phosphorus trihydride.
<h3>What type of bond is PH3?</h3>
The electronegativity of PH3 found in the Periodic Table of the Period attracts covalent electron pairs and creates covalent bonds. However, because the electrons are not bound, asymmetrical rate distribution occurs. Therefore, PH3 is a polar molecule with a non-polar covalent bond and currently has no polar bond.
<h3 /><h3>What defines a covalent bond?</h3>
A covalent bond consists of sharing one or more electron pairs between two atoms. These electrons are attracted to two nuclei at the same time. Covalent bonds are formed when the difference in electronegativity between two atoms is too small for electron transfer to form ions.
Click here for more information on covalent bonds brainly.com/question/12732708
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