The computation would be:moles = mass/ Molar Mass, but we are looking for the mass, so rearranging, will give us: mass = moles x MM
Q = moles x Hf
Q = (mass/MM) x Hf
mass = (Q x MM) / Hf
= (1.50-kJ x 18.0-g/mol) / 6.01-kJ/mol
=4.49 g H20 is the answer
Answer:
option c .
Explanation:
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The minimum initial speed of the dart so that the combination makes a complete circular loop after the collision is 58.5 m/s.
<h3>Minimum speed for the object not fall out of the circle</h3>
The minimum speed if given by tension in the wire;
T + mg = ma
T + mg = m(v²)/R
tension must be zero for the object not fall
0 + mg = mv²/R
v = √(Rg)
<h3>Final speed of the two mass after collision</h3>
Use the principle of conservation of energy
K.Ef = K.Ei + P.E
¹/₂mvf² = ¹/₂mv² + mg(2R)
¹/₂vf² = ¹/₂v² + g(2R)
¹/₂vf² = ¹/₂(Rg) + g(2R)
vf² = Rg + 4Rg
vf² = 5Rg
vf = √(5Rg)
vf = √(5 x 2.8 x 9.8)
vf = 11.7 m/s
<h3>Initial speed of the dart</h3>
Apply principle of conservation of linear momentum for inelastic collision;
5v = vf(20 + 5)
5v = 11.7(25)
5v = 292.5
v = 58.5 m/s
Learn more about linear momentum here: brainly.com/question/7538238
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