1.505 times 10^23 Na atoms
1 answer:
5.75g
Explanation:
Given parameters:
Number of atoms = 1.505 x 10²³atoms
let us find the number of moles and mass of this atom.
Solution:
The mole is convenient unit for reporting measurements in chemistry. It allows us to make mathematical calculations:
one mole of substance contains 6.02 x 10²³atoms
Number of moles of Na given = = 0.25moles
Mass of Na atom given = number of moles x molar mass
Molar mass of Na= 23g/mole
Mass of Na = 0.25 x 23 = 5.75g
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Number of moles brainly.com/question/1841136
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511.2 grams of chlorine gas consumed (with excess H-) when
1,342.0 kJ of energy is released from the system.
<h3></h3><h3>What is an exothermic reaction?</h3>In thermochemistry, an exothermic reaction is a "reaction for which the overall standard enthalpy change ΔH⚬ is negative."
Given that 1 mole of chlorine releases -184.6 energy.
Then, we have to find the number of moles of chlorine when 1,342.0 kJ of energy is released from the system.
So, calculating number of moles of chlorine.
Moles =
Moles = 7.2 mole
Now, calculating number mass of chlorine.
Mass = 7.2 mole x 71 g/mole
Mass = 511.2 gram
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a. t=0.553 s
b. vox(horizontal speed) = 3.62 m/s
<h3>Further explanation</h3>Given
h = 1.5 m
x = 2 m
Required
a. time
b. vo=initial speed
Solution
Free fall motion
a. h = 1/2 gt²(vertical motion=h=voyt+1/2gt²⇒voy = 0)
t = √2h/g
t = √2.1.5/9.8
t=0.553 s
b. x=vox.t(horizontal motion)
vox=x/t
vox=2/0.553
vox=3.62 m/s