Alloys

Q.

Stainless steel is an alloy of which elements?

Q.

Brass is a mixture of ______.

Q. Alloys are homogeneous mixtures.

1. False
2. True

Q.

Assertion- Alloys are commonly used in electrical heating devices like electric iron and heater.

Reason- The resistivity of an alloy is generally higher than that of its constituent metals but the alloys have low melting points than their constituent metals.

Choose the correct option:

1. Both assertion and reason are true and reason is the correct explanation of assertion.

2. Both assertion and reason are true but reason is not the correct explanation of assertion.

3. Assertion is true but reason is false

4. Assertion is false but reason is true

Q. Brass is a mixture of

1. 30% Cu and 70% Pb
2. 70% Cu and 30% Zn
3. 30% Cu and 70% Sn
4. 70% Cu and 30% Pb

Q.

What is it called when you mix two metals together ?

Q.

List three Characteristics of alloys.

Q.

Stainless steel is an alloy which has iron as major constituent.

1. True

2. False

Q. Cu, Ag, and Au are known as coinage metals because they ____

1. form alloys easily
2. have high melting points
3. were earlier used to mint coins
4. all shines

Q.

What are alloys? List two properties of alloys.

Q.

Name the following:

An alloy of iron and nickel.

Q.

Stainless steel is a very useful material for our life. In stainless steel, iron is mixed with

1. $\mathrm{Ni}$ and $\mathrm{Cr}$

2. $\mathrm{Cu}$ and $\mathrm{Cr}$

3. $\mathrm{Ni}$ and $\mathrm{Cu}$

4. $\mathrm{Cu}$ and $\mathrm{Au}$

Q.

Steel , Bronze , Brass are alloys

1. True
2. False

Q.

Why is stainless steel a poor conductor of heat?

Q.

Cooling coils in refrigerators are made of _____________ to conduct away the heat.

Q.

Identify which of the following is homogenous mixture or heterogeneous one. Also identify the type of constituents in mixture (e.g. gas in gas, gas in liquid, gas in solid etc.)
a. Air ($N_2+O_2$)
b. Water and Oil
c. Hydrogen in Palladium
d. Aerated Water ($C{O}_2+H_{2}O$ )
e. Chalk in water
f. Ethyl Alcohol in Water
g. Alloys e.g. brass
h. Sand + ammonium chloride
i. Mercury in amalgamated Zinc

[5 MARKS]

Q.

_________is an example of solid in solid solution

A cold drinks

B German silver

C dust particles in air

D fog

Q.

Alloy is considered a mixture. Give 3 reason to support your answer

Q.

One of the following represents the solution of solid in a solid. This one is :

(a) boron (b) brass (c) beryllium (d) bread

Q. Question 13
The 'sea-water' can be classified as a homogeneous as well as a heterogeneous mixture. Comment.

Q.

Is Titanium stronger than Stainless Steel?

Q.

Which of the following is a ferrous alloy?

1. Brass

2. Steel

3. Solder

4. Magnalium

Q.

18 carat gold is a mixture.

1. True
2. False

Q.

Give example for alloys

Q.

The alloy of copper and zinc is known as__i__ and the alloy of carbon and iron is known as__ii__.

Which alternative completes the above statement?

1. 

2. 

3. 

4. 

Q. Question 26
Alloys are homogeneous mixtures of a metal with a metal or nonmetal. Which among the following alloys contain non-metal as one of its constituents?
(a) Brass
(b) Bronze
(c) Amalgam
(d) Steel

Q. What type of mixture is steel?

1. Solid-liquid heterogeneous mixture
2. Solid-solid heterogeneous mixture
3. Solid-solid homogeneous mixture
4. Pure substance

Q. Option 15
Stainless steel is very useful material for our life. In stainless steel, iron is mixed with
(a) $\text{Ni}$ and $\text{Cr}$
(b) $\text{Cu}$ and $\text{Cr}$
(c) $\text{Ni}$ and $\text{Cu}$
(d) $\text{Cu}$ and $\text{Au}$

Q.

Ferrites are alloys of iron

1. True
2. False

Q. Which alloy steel is used for making permanent magnets ?