Answer:
B. The motorcyclist traveled southeast along a highway at 55 mph and reached the campsite in less than the two-hour estimated time.
Explanation:
<em>Velocity </em>is the rate at which an object changes position in a specific direction. It has both <em>magnitude and direction.</em>
Travelling <em>southeast</em> at <em>55 mph</em> is a <em>velocity</em>. It gives both speed and direction.
Statements A., B., and C. give the direction but not the speed.
Answer:
Explanation: A chemical change is a reaction in which chemical composition of the substance changes. Some bonds are broken and some new bonds are formed.
The reactants are written in terms of their chemical formula on the left hand side and the products are written in terms of their chemical formula on right hand side with a arrow in between. The chemical symbols are followed by their physical states such as (l) for liquid, (s) for solid, (g) for gas and (aq) for aqueous.
Thus the only reaction producing a gas is
Answer:
71820 J
Explanation:
From the question given above, the following data were obtained:
Mass (M) = 1.05 Kg
Initial Temperature (T₁) = 23 °C
Final temperature (T₂) = 99 °C
Heat (Q) required =?
Next, we shall determine the change in temperature. This can be obtained as follow:
Initial Temperature (T₁) = 23 °C
Final temperature (T₂) = 99 °C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 99 – 23
ΔT = 76 °C
Finally, we shall determine the heat required. This can be obtained as follow:
Mass (M) = 1.05 Kg
Change in temperature (ΔT) = 76 °C
Specific heat capacity (C) of aluminum = 900 J/KgºC
Heat (Q) required =?
Q = MCΔT
Q = 1.05 × 900 × 76
Q = 71820 J
Thus, 71820 J heat energy is required.
The balanced chemical equation for the above reaction is as follows ;
Ca(OH)2 + 2HCl —> CaCl2 + 2H2O
Stoichiometry of Ca(OH)2 to HCl is 1:2
Number of Ca(OH)2 moles present - 0.001 mol/L / 1000 mL/L x 25 mL
Number of Ca(OH)2 moles = 2.5 x 10^(-5) mol
Number of HCl moles needed for neutralisation = 2.5 x 10^(-5) mol x2 = 5 x 10 ^(-5) mol
The molarity of HCl solution is 0.005 M
The solution contains 0.005 mol in 1000 mL
Therefore volume of 5x10^(-5) mol in = 1000/0.005 x 5 x 10^(-5) mol = 10 mL
10 mL of HCl is needed for neutralisation
Minnesota receivers arctic air when the polar jet stream moves south across Canada.