Which one of the following acids, is formed during the change of milk into curd?
Correct Answer:
(D)
Lactic acid
When pasteurized milk is heated to a temperature of 30-40oC or even at room temperature and a small amount of old curd or whey is added to it, the lactobacillus (bacteria) in that curd or whey sample starts to grow. They convert the lactose into lactic acid, which imparts the sour taste to curd.
Ques:
22
The predominant organic acid in grapes is –
Correct Answer:
(D)
Tartaric acid
Tartaric acid is the predominant organic acid in grapes. It is a white crystalline diprotic acid.
Ques:
23
For human nutrition, tomatoes are a rich source of
Correct Answer:
(C)
Citric acid
Tomato contains mainly citric acid and malic acid. Due to which, it also acts as ant-acid. It also contains oxalic acid which is found less in quantity.
Ques:
24
Which one of the following organic acids is abundant in grapes, tamarind and banana?
Correct Answer:
(D)
Tartaric acid
Tartaric acid is found in abundance in grapes, tamarind and banana. This acid is used as regulator and antioxidant in food items.
Ques:
25
Which acid is used in photography–
Correct Answer:
(B)
Oxalic acid
Oxalic acid is used in photography. Formic acid is found in ants. Citric acid is found in lemon and acetic acid is found in vinegar.
Ques:
26
Which one of the following acids is used in the manufacturing of baking powder ?
Correct Answer:
(C)
Tartaric Acid
Tartaric acid is used in the manufacturing of baking powder. This tartaric acid occurs naturally in many plants particularly in grapes, bananas and tamarinds. It is commonly combined with baking soda to function as a leavening agent in recipes and is one of the main acids found in wine.
Ques:
27
Which of the following is a natural fuel?
Correct Answer:
(D)
Petroleum
The petroleum products are subject to natural fuel. They are made from the fossils buried within the earth. Other options coke and tar can be achieved by destructive distillation of coal or wood, while coal gas can be created artificially.
Ques:
28
Which of the following fossil fuels is the cleanest fuel ?
Correct Answer:
(C)
Natural gas
The use of natural gas in power generation provides a cleaner alternative to coal and other fossil fuels, reducing carbon and other emissions and resulting in both immediate and long-term benefits for public health and the environment.
Ques:
29
Which of the following is a fossil fuel?
Correct Answer:
(D)
Natural gas
Fossil fuels, including coal, oil and natural gas are currently the world’s primary energy sources. The fossil fuels formed from the organic material over the course of millions of years have fuelled the global economy over the past century. Yet the fossil fuels are finite resources and they can also irreparably harm the environment.
Ques:
30
Which one of the following has the highest fuel value ?
Correct Answer:
(A)
Hydrogen
The heating value of a fuel is the amount of heat that is obtained after one gram (1gm) of fuel is burnt completely in air or oxygen. Hydrogen has the highest heating value among all fuels. Hydrogen is used as a rocket fuel and in burner producing high temperature. The fuel value of hydrogen gas is 150, charcoal 33, natural gas 50-55 and gasoline 45. Hydrogen gas was first artificially produced in the early 16th century. Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance.