Answer:
665 kJ
Explanation:
We assume that carbohydrates and protein each have 4 kilocalories per gram, and that fat has 9 kilocalories per gram. Then the number of kilocalories in the peanut butter is ...
4(6 +9) +9(11) = 159 . . . . kilocalories
Each kilocalorie translates to 4.184 kilojoules, so the total is ...
(159 kCal)(4.184 kJ/kCal) = 665.256 kJ
2 Tbsp of crunchy peanut butter contains about 665 kJ of energy.
Answer:
the volume of 5.0 g CO2 is 2.6L
CO2 at tsp
Percent by mass of platinum in white gold = 100% - 45% = 55%
We let x be the mass of the white which is 45% gold and 55% platinum.
Mass of gold in white gold = m x 0.45
where m is the total mass.
From the given above, we formulate the equation that would allow us to determine the mass of white gold.
154 = x (0.45)
x = 342.22 g
Then, we determine the amount of platinum.
mass of platinum = (342.22 g)(0.55)
mass of platinum = 188.22 grams
Thus, 188.22 grams of platinum is needed.
Explanation:
Y has 13 protons and we know that Aluminium (Al) too has 13 protons.
So , element Y = Aluminium
• In an element , no. of protons = no. of electrons. So , Y has 13 electrons.
• Mass no. of Y (Aluminium) = 27.
• Also we know that ,
Mass number = no. of protons + no. of neutrons
So,
No. of neutrons = 27 - 13 = 14
• Valence electrons are the electrons which are present in the outermost shell of an element.
Electronic Configuration of Y = 2,8,3
So, Y has 3 valence electrons.
• We know that Y is Aluminium & Aluminium is a metal. So , Y is a metal.
• Valency of Y = +3
