Answer:
14175 j heat released.
Explanation:
Given data:
Mass of aluminium = 350.0 g
Initial temperature = 70.0°C
Final temperature = 25.0°C
Specific heat capacity of Aluminium = 0.9 j/g.°C
Heat changed = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
Heat change:
ΔT = Final temperature - initial temperature
ΔT = 25.0°C - 70°C
ΔT = -45°C
Q = m.c. ΔT
Q = 350 g × 0.9 j/g.°C × -45°C
Q = -14175 j
What you were given is the balanced chemical equation
B
Explanation:
Burning is a chemical change and cutting grass is a physical change
Answer:
8.2 x 106^-11
Explanation:
To begin this problem you must remember the basic rule of scientific notation, which is, must be between 1-10. .000000000082 is much smaller than 1. However by moving the decimal 11 spots to the right, we can make it 8.2
Continue to move the decimal to the right until the value is in the 1-10 range. Make sure to count the moves to the right.
Once the decimal is in the right spot count the spots moved.
Since the number is wayyy smaller than the answer given the number will be negative 10^-11, in order to make it what is was before.
Answer:
C) 0.121 M
Explanation:
HCl + H₂O = H₃O⁺ + OH⁻
.121M .121M
HCl is a strong acid . It will dissociate almost 100 % so the concentration of acid and hydronium ion formed will be equal . It is to be noted that hydronium ion is formed due to association of H⁺ and H₂O . H⁺ is formed due to ionisation of HCl .
So concentrtion of hydronium ion ( H₃O⁺ ) will be .121 M.