Answer:
Qm = -55.8Kj/mole
Explanation:
NaOH(aq) + HNO₃(aq) => NaNO₃(aq) + H₂O(l)
Qm = (mc∆T)water /moles acid
Given => 100ml(0.300M) NaOH(aq) + 100ml(0.300M)HNO₃(aq)
=> 0.03mole NaOH(aq) + 0.03mole HNO₃(aq)
=> 0.03mole NaNO₃(aq) + 0.03mole H₂O(l)
ΔH⁰rxn = [(200ml)(1.00cal/g∙°C)(37 – 35)°C]water / 0.03mole HNO₃
= 13,333 cal/mole x 4.184J/cal = 55,787J/mol = 55.8Kj/mole (exothermic)*
Heat of reactions comes from formation of H-Oxy bonds on formation of water of reaction and heats the 200ml of solvent water from 35⁰C to 37⁰C.
No because you are supposed to do this

T for time and V for velocity or acceleration so what you do is take the two numbers
D= 3/12 it goes 12 meters every 3 seconds so you devide 12/3

So for every second the ball roles 4 meters!
Hope this helps! :)
<span>We can use the heat
equation,
Q = mcΔT </span>
<span>Where Q is
the amount of energy transferred (J), m is the mass of the
substance (kg), c is the specific heat (J g</span>⁻¹ °C⁻<span>¹) and ΔT is the temperature
difference (°C).</span>
Density = mass / volume
The density of water = 0.997 g/mL
<span>Hence mass of 1.25 L (1250 mL) of water = 0.997 g/mL x 1250 mL</span>
<span> = 1246.25 g</span>
Specific heat capacity of water = 4.186 J<span>/ g °C.</span>
Let's assume that there is no heat loss to the surrounding and the final temperature is T.
By applying the equation,
5430 J = 1246.25 g x 4.186 J/ g °C x (T - 23) °C
(T - 23) °C = 5430 J / 1246.25 g x 4.186 J/ g °C
(T - 23) °C = 1.04 °C
T = 1.04 °C + 23 °C
T = 24.04 °C
Hence, the final temperature of the water is 24.04 °C.
Answer:
C. Double Replacement
Explanation:
A. Wrong because SR uses a compound and element. This equation is a compound and compound.
B. Wrong because it does not have O2 in the formula. All combustion reactions must have O2.
C. Correct because it is a compound reacting with a compound.
D. Wrong because the reactants did not form a single product. ex. (x + y > xy)
E. Wrong because the equation did not start with a single compound and break down. ex. (xy > x + y)
Nickel contains more atoms.
<u>Explanation:</u>
Number of atoms is determined by the Avogadro number.
1 mole of substance contains 6.022 X 10²³ atoms.
Given:
Mass of Nickel, Ni = 3.89g
Molecular weight of Ni = 58.6934g
Number of moles of Ni = 3.89/58.6934g
Number of atoms of Ni = 
Number of atoms of Ni = 0.39 X 10²³
Mass of silver, Ag = 6.61g
Molecular weight of Ag = 107.8682g
Number of moles of Ag = 6.61/107.8682
Number of atoms of Ag = 
Number of atoms of Ag = 0.36 X 10²³
Therefore, Nickel contains for atoms.