1) Answer: A hot pack feels warm when chemicals in it combine.
Explanation: Reactions or process in which heat is released(produced) are known as exothermic reactions or process and those in which the heat is absorbed are known as endothermic reactions or process.
If a beaker feels cools when chemical in it react then it means the chemicals have absorbed the heat energy from its surroundings and so it is an example of an endothermic process.
A hot pack feels warm when chemicals in it combine means the energy is released in the chemical reaction and so it is an example of an exothermic process.
Plants use the sun's energy for photosynthesis which is a process of forming food for the plants. Energy acts as a reactant in this process and so it is an example of endothermic process.
Frying an egg by heating it on a stove is an example of an endothermic process as the heat is required to fry the egg.
So, the only exothermic process is the second one, "A hot pack feels warm when chemicals in it combine."
2) In the given equation, heat is written as a product means the heat is released in the equation and so it is an example of an exothermic reaction.
So, the correct choice is the last one " It is exothermic because energy is released."
Answer:hemoglobin that has a high affinity for oxygen
Explanation:
Haemoglobin is the oxygen carrying pigment in blood. It performs this function because of the presence of iron at the center of the haemoglobin which coordinates reversibly with oxygen thereby aiding delivery of oxygen to cells. At high altitudes where air is thinner and the partial pressure of oxygen is lower than sea level, haemoglobin must develop a greater affinity for oxygen in order to carry the scarce oxygen to cells.
Answer:
17.934 kg of water
Explanation:
If balanced equation is not given; this format can come in handy.
For any alkane of the type : CₙH₂ₙ₊₂ , it's combustion reaction will follow:
2CₙH₂ₙ₊₂ + (3n+1) O₂ → (2n)CO₂ + 2(n+1) H₂O
For butane:
2C₄H₁₀(g) + 13O₂(g) → 8CO₂(g) + 10H₂O(l)
2 moles of butane gives 10 moles of water.
1 mol of any substance has Avogadro number(N) of molecules in it( 6.022 x 10²³)
Mass of 1 mole of any substance is equal to it's molar mass
So, if 2 x N molecules of butane gives 10 x 18 g of water.
Then 1.2 x 10²⁶ molecules will give:

= 17.934 x 10³ g of water
= 17.934 kg of water
Your Answer Will Be Intensive Property
Answer:
+1
Explanation:
Electrochemistry. In oxidation–reduction (redox) reactions, electrons are transferred from one A redox reaction is balanced when the number of electrons lost by the reductant Hg(l)∣Hg2Cl2(s)∣Cl−(aq) ∥ Cd2+(aq)∣Cd(s).
As is evident from the Stock number, mercury has an oxidation state of +1. This makes sense, as chlorine usually has an oxidation state of -1.