Answer:
87.5 mi/hr
Explanation:
Because a = Δv / Δt (a = vf - vi/ Δt), we need to find the acceleration first to know the change in velocity so we can determine the final velocity.
vf = 60 mi/hr
vi = 0 mi/hr
Δt = 8 secs
a = vf - vi/ Δt
= 60 mi/hr - 0 mi/hr/ 8 secs
= 60 mi/hr / 8 secs
= 7.5 mi/hr^2
Now that we know the acceleration of the car is 7. 5 mi/hr^2, we can substitute it in the acceleration formula to find the final velocity when the initial velocity is 50 mi/hr after 5 secs.
vi = 50 mi/ hr
Δt = 5 secs
a = 7.5 mi/ hr^2
a = vf - vi/ Δt
7.5 = vf - 50 mi/hr / 5 secs
37.5 = vf - 50
87.5 mi/ hr = vf
Answer:
2.03125g of acetylene
Explanation:
First thing's first, we have to write out the balanced chemical equation;
CaC2(s) + 2H2O(l) → Ca(OH)2(aq) + C2H2(g)
Water is in excess, so CAC2 is our limiting reactant. i.e it determines the amount of product that would be formed.
1 mol of CaC2 produces 1 mol of C2H2
In terms of mass;
Mass = Number of moles * Molar mass
where the molar mass of the elements are;
Ca = 40g/mol
C = 12g/mol
H = 1g/mol
CaC2 = 40+ (2*12) = 64g/mol
C2H2 =( 2 * 12) + ( 2 * 1) = 26g/mol
64g (1 * 64g/mol) of CaC2 produces 26g ( 1mol * 26g/mol) of C2H2
5g would produce x?
64 = 26
5 = x
Upon solving for x we have;
x = (5 * 26) / 64
x = 2.03125g
Answer:
Knowing this, researchers from the University of Southern Denmark decided to investigate the size of these hypothetical hidden particles. According to the team, dark matter could weigh more than 10 billion billion (10^9) times more than a proton.
Explanation:
If this is true, a single dark matter particle could weigh about 1 microgram, which is about one-third the mass of a human cell (a typical human cell weighs about 3.5 micrograms), and right under the threshold for a particle to become a black hole.
Dipyrithione is a chemical with formula, C₁₀H₈N₂O₂S₂. This means that each molecule of the substance has two (2) atoms of nitrogen. By using the dimensional analysis and Avogadro's number, equal to 6.022 x 10²³, we calculate for the answer as shown below.
n = (8.2 x 10²⁴ atoms N)(1 molecule dipyrithione/ 2 atoms of N)(1 mole dipyrithione/ 6.022 x 10²³ molecules dipyrithione)
Simplifying,
n = 6.8 moles dipyrithione
<em>ANSWER: 6.8 moles</em>
