The best answer is letter A.
The main factors that change the speed of enzymatic reactions are temperature, pH and substrate concentration (quantity). <span>There are enzymes that need other associated molecules to work. These molecules are called enzyme co-factors. They can be organic ions like mineral salts.</span>
Potassium metal + Chlorine Gas -------->
Potassium Chloride<span>
The chemical equation using symbols and formula is
<span>K (s) + </span></span><span><span><span><span>Cl</span>2</span> </span><span>(g) ---------> 2KCl (s)</span></span>
Ice cream will have a physical change because you can re freeze it and it will still be ice cream
Density = Mass / Volume
Mass = Density * Volume
Mass = 45 * 7 * 8 * 10
Mass = 25,200 grams
Answer:
666,480 Joules or 669.48 kJ
Explanation:
We are given;
- Volume of water as 2.0L or 2000 ml
but, density of water is 1 g/ml
- Therefore, mass of water is 2000 g
- Initial temperature as 20 °C
- Final temperature as 99.7° C
Required to determine the heat change
We know that ;
Heat change = Mass × Temperature change × specific heat
In this case;
Specific heat of water is 4.2 J/g°C
Temperature change is 79.7 °C
Therefore;
Heat change = 2000 g × 79.7 °C × 4.2 J/g°C
= 669,480 Joules 0r 669.48 kJ
Thus, the heat change involved is 666,480 Joules or 669.48 kJ
