Answer:
element S is argon and element T is potassium.
4. B
5. D
Explanation:
in an element in periodic table number of elctrons and protons are same.
4. since element S has 18 protons so its atomic number must be 18 so the element is Argon which is the last element of period 4 so the next element will go to period 4 with one extra shell and since the atomic number of next element is 19 the element is Potassium. therefore T is Potassium.
5. number of nucleons in an atom is the number of protons and neutons combined together in an nucleus
The intestines
By the time food has reached the intestines, it has already passed through the gizzard (where it is ground up) and has nutritious pieces absorbed before waste is passed to the excretory system.
C7H14 + 10.5 O2 -> 7 CO2 + 7 H2O
Or, if whole numbers must be used:
2 C7H14 + 21 O2 -> 14 CO2 + 7 H2O
Explanation:
(a) the sublimation of dry ice [conversion of CO2(s) directly to CO2(g)]
The balanced equation is given as;
CO2(s) --> CO2(g)
This reaction is endothermic, hence; Heat is a reactant and is needed to start the reaction.
(b) the reaction of 1 mol of sulfur dioxide with oxygen.
The balanced equation is given as;
2SO2 + O2 --> 2SO3
This reaction is exothermic, hence; Heat is a product and is given off by the reaction.
