Answer is: A) Sr (strontium).
The reactivity series<span> is a series of metals from highest to lowest reactivity.</span><span> Metal higher in the reactivity series will displace another.
</span>Strontium is only higher in this group from magnesium. Strontium is stronger reducing agent than magnesium, gives electrons easier.
In thermal cracking, high temperatures (typically in the range of 450°C to 750°C) and pressures (up to about 70 atmospheres) are used to break the large hydrocarbons into smaller ones. Thermal cracking gives mixtures of products containing high proportions of hydrocarbons with double bonds - alkenes.
Carbon dioxide is a compound. Oxygen is an element. A compound is 2 or more elements chemically combined. An element is a pure substance. A mixture is combining two or more different compounds/elements.
Answer:
energy required is 0.247kJ
Explanation:
The formula to use is Energy = nRdT;
Where n is number of mole
R is the molar gas constant
dT is the change in temperature
n = reacting mass of mercury / molar mass of mercury = 27.4/200.59 = 0.137
dT = final temperature - initial temperature = 376.20 - 158.30 = 217.90K
R = 8.314Jper mol per Kelvin
Energy = 0.137 x 8.314 x 217.90 = 247.12J
Energy in kJ= 247.12/1000= 0.247kJ
