Ethereum Developer Solidity Smart Contract Development

Question 1

Which Solidity keyword is used to declare a function that cannot modify contract state?

Accepted Answer

view

Answer

pure

Answer

constant

Answer

immutable

Question 2

What is the purpose of the `payable` keyword in a Solidity function?

Accepted Answer

It allows the function to receive Ether

Answer

It makes the function free to call

Answer

It locks the function from being overridden

Answer

It enables the function to return Ether

Question 3

Which Solidity data type is used to store Ethereum addresses?

Accepted Answer

address

Answer

bytes20

Answer

uint160

Answer

string

Question 4

What does the `require` statement do in Solidity when its condition is false?

Accepted Answer

Reverts the transaction and refunds unused gas

Answer

Emits an error event

Answer

Pauses the contract

Answer

Returns a false boolean

Question 5

In Solidity, what is a `mapping`?

Accepted Answer

A hash table that maps keys to values

Answer

An ordered array of key-value pairs

Answer

A linked list data structure

Answer

A pointer to a storage slot

Question 6

Which visibility specifier restricts a function to be called only within the contract itself?

Accepted Answer

private

Answer

internal

Answer

external

Answer

public