2.05 × 10²³ formula units
Given data:Mass of AgF = 43.15 gNumber of formula units = ?Solution:Number of moles of AgF:Number of moles = mass/ molar massNumber of moles = 43.15 g/ 126.87 g/molNumber of moles = 0.34 molNow Number of formula units will be determine by using Avogadro number.It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.The number 6.022 × 10²³ is called Avogadro number1 mole = 6.022 × 10²³ formula units0.34 mol × 6.022 × 10²³ formula units2.05 × 10²³ formula units
Answer:
35.5450 will be rounded to 35.55
Explanation:
=35.5450
if the last digit is less than 5 then it will be ignored
=35.545
when the dropping digit is 5 then the retaining digit will increse by a factor of 1
=35.55
i hope this will help you
Glaciers, groundwater, streams are three of them
Answer:
The ΔH of the reaction is + 12.45 KJ/mol
Explanation:
Mass of water= 100ml = 100g. (You should always assume 1cm3 of water as 1g)
heat capacity of water = 4.18 Jk-1 Mol-1
Change in temperature = (19.86 - 25.00) = -5.14 K (This is an endothermic reaction because of the fall in temperature)
Molar mass of NaHCO3 = 84 g/mol
Mole of NaHCO3 = 14.5 / 84 = 0.173 mol
Step 1 : Calculate the heat energy (Q) lost by the water.
Q = M x C x ΔT
Q = -100 x 4.18 x (-5.14)
Q = 2148.5 joules
Q = 2.1485 K J
Step 2: Calculating the ΔH of the reaction?
ΔH = Q / number of moles of NaHCO3
ΔH = 2.1485 / 0.173
ΔH = 12.42 KJ/mol
Answer: b- it is always a substance
Explanation: matter can be any liquid, gas, or solid that takes up space so the answer cannot be C or D. For answer number A to be true, you would have to remove the word more, because matter just has mass and takes up space it does not have "more mass"
