1. How is the modern periodic table organized? Increasing atomic number
2. What information about an atom's properties can you read from the periodic table? Metal or not metal. Does it want to gain or lose electrons
3. How are the relationships of elements in a group different from the relationships of elements in a period? a group will have similar properties A period will have different properties
4. Would you expect Strontium (Sr) to be more like potassium (K) or bromine (Br)?
potassium
5. Barium (Ba) is in Group 2. Recall that atoms in Group 1 lose one electron to form ions with a 1+ charge. What type of ion does barium form? Ba+2
Since the density of water is 1 g /mL, hence there is 100
g of H2O. So total mass is:
m = 100 g + 5 g = 105 g
=> The heat of reaction can be calculated using the
formula:
δhrxn = m C ΔT
where m is mass, C is heap capacity and ΔT is change in
temperature = negative since there is a decrease
δhrxn = 105 g * 4.18 J/g°C * (-2.30°C)
δhrxn = -1,009.47 J
=> However this is still in units of J, so calculate
the number of moles of NaCl.
moles NaCl = 5 g / (58.44 g / mol)
moles NaCl = 0.0856 mol
=> So the heat of reaction per mole is:
δhrxn = -1,009.47 J / 0.0856 mol
δhrxn = -11,798.69 J/mol = -11.8 kJ/mol
Answer:
A...................................
