Environmental Hazards are usually any chemicals that donot naturally occur to exist anywhere and are usually made in the fields of industry or experimental sciences
So if you happen for example to throw a bit of mercury in some river while being in a school trip then this is an environmental hazard created by humans
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
The variable that is measured as data in an experiment is 1. the dependent variable.
The variables that are held constant in an experiment are 2. the controlled variables.
The variable that is changed by the experimenter is 5. the independent variable.
A count or measurement recorded during an experiment is 4. quantitative data.
Descriptions or observations during an experiment are 3. qualitative data.
Answer: The answer is A. A conductor that allows electricity to flow easily
