1. Reaction in which heat is released
2. Reaction in which heat is absorbed
3. Reaction in which neither heat is released nor absorbed
4. None of these
Option “A” is correct An exothermic reaction is a chemical reaction that releases energy by light or heat. It is the opposite of an endothermic reaction. Expressed by chemical equation: reactants → products + energy.
302. What are the main components of Brass Alloy?
1. Copper and Zinc
2. Copper and Strontium
3. Copper, Zinc and Nickel
4. Copper and Nickel
Option “A” is correct Brass is a metallic alloy that is made of copper and zinc. Brass is commonly used for decorative purposes primarily because of its resemblance to gold. It is also a commonly used to make musical instruments due to its high workability and durability.
303. What is formed when Magnesium is burnt?
1. Baking Soda
2. Calcium Carbonate
3. Ash
4. Vinegar
Option “C” is correct When the magnesium metal burns it reacts with oxygen found in the air to form Magnesium Oxide. Oxygen and magnesium combine in a chemical reaction to form this compound. After it burns, it forms a white ash of the magnesium oxide.
304. Bronze is an alloy of copper and-
1. Tin
2. Aluminum
3. Silver
4. Nickel
Option “A” is correct Bronze is an alloy made up of Copper and another metal Tin. Compositions may very but most modern bronze is 88% Copper and 12% Tin
305. The Chemical formula of Ammonium dichromate is _____
Option “A” is correct Ammonium dichromate is the inorganic compound with the formula (NH4)2Cr2O7.
306. The residual attractive or repulsive forces between molecules or atomic groups that do not arise from a covalent bond, or ionic bonds is called _____.
1. Neutral Bond
2. Non Polar Bond
3. Electro Valence bond
4. Van der Walls bond
Option “D” is correct The residual attractive or repulsive forces between molecules or atomic groups that do not arise from a covalent bond, or ionic bonds is called Van der Walls bond.
307. Chromite is an ore/mineral of –
1. Zinc
2. Uranium
3. Chromium
4. Titanium
Option “C” is correct Chromite is the only ore of chromium, a metal essential for making stainless steel, nichrome, chrome plating, pigments, refractories, chemicals and pharmaceuticals.
308. Which among the following has the maximum density?
1. Water
2. Ice
3. Ethylene
4. Acetone
Option “A” is correct Water has maximum density.
309. What happens in an oxidation reaction?
1. Protons are lost.
2. Electrons are lost
3. Neutrons are lost
4. Electrons are gained
Option “B” is correct Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion.
310. Haematite is an ore/mineral of-
1. Zinc
2. Iron
3. Lead
4. Manganese
Option “B” is correct Haematite is an ore of Iron.
Q. 1. Ribosomes are made up of..
1. Protein and RNA
2. Protein and DNA
3. Carbohydrates
4. Cellulose
Q. 2. Electron transport chain occur at …
1. Protein fibre
2. Cellulose
3. mitochondrial inner membrane
4. Callose
banothshailu@123gemil.come
Which instrument is used to capture the purity of milk?
(A) hydrometer
(B). Isometric
(C). Lacto meter
Lactometer
I Love chemical…it’s my favourite subject..mere iss mein se hmesha hi boht ache marks aate hai….and my interest is also in chemistry…
Protein and RNA
Protein and RNA
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