Tasting it and touching it are both potentially dangerous for a start haha. SO DONT DO THOSE ONES.
Litmus paper is a good choice because its colour changes based on the presence of an acid or base.
Phenolphthalein is an acid-base indicator and does a similar thing to litmus.
Litmus paper and phenolphthalein are the right choices
Answer:
c = 0.898 J/g.°C
Explanation:
1) Given data:
Mass of water = 23.0 g
Initial temperature = 25.4°C
Final temperature = 42.8° C
Heat absorbed = ?
Solution:
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
Specific heat capacity of water is 4.18 J/g°C
ΔT = 42.8°C - 25.4°C
ΔT = 17.4°C
Q = 23.0 g × × 4.18 J/g°C × 17.4°C
Q = 1672.84 j
2) Given data:
Mass of metal = 120.7 g
Initial temperature = 90.5°C
Final temperature = 25.7 ° C
Heat released = 7020 J
Specific heat capacity of metal = ?
Solution:
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
ΔT = 25.7°C - 90.5°C
ΔT = -64.8°C
7020 J = 120.7 g × c × -64.8°C
7020 J = -7821.36 g.°C × c
c = 7020 J / -7821.36 g.°C
c = 0.898 J/g.°C
Negative sign shows heat is released.
I think the answer is 1. HF
Amino acids are the basic parts of proteins
<h2> The amount of Hcn formed in grams is = 0.06223 grams</h2><h3> calculation</h3>
write the equation for reaction
that is; KCn + HCl → KCl + HCn
step 1:find the moles of KCn reacted
moles of KCn = mass of KCn/molar mass of KCn( 65.12 g/mol)
= 0.150 g/ 65.12 g/mol =2.303 x10^-3 moles
step 2: use the mole ratio between KCn :HCn which is 1:1 to determine the moles of HCn which is also 2.303 x 10^-3 moles
step 3: find the mass of HCn =moles of HCn x molar mass of HCn
= 2.303 x10^-3 x 27. 02 =0.06223 grams
