Ethereum vs Bitcoin differences in Blockchain / Solidity - Practice Questions

Challenge - 5 Problems

🧠 Conceptual

intermediate

Primary Purpose of Ethereum vs Bitcoin

What is the main difference in the primary purpose between Ethereum and Bitcoin?

A Bitcoin is mainly a digital currency, while Ethereum is a platform for decentralized applications.

B Ethereum is only used for digital currency, Bitcoin is for smart contracts.

C Both Ethereum and Bitcoin are only used for storing value with no other functions.

D Bitcoin is a platform for decentralized apps, Ethereum is just a digital currency.

💡 Hint

Think about what you can build on Ethereum beyond just sending money.

Bitcoin was created as a digital currency to transfer value securely. Ethereum was designed as a platform to build decentralized applications using smart contracts.

❓ Predict Output

intermediate

Ethereum Smart Contract Gas Cost Calculation

Given this simplified Ethereum smart contract function call, what is the total gas cost if the base cost is 21000 and the function adds 15000 gas?

Blockchain / Solidity

base_gas = 21000
function_gas = 15000
total_gas = base_gas + function_gas
print(total_gas)

A 36000

B 21000

C 15000

D 19000

💡 Hint

Add the base gas and function gas costs.

The total gas cost is the sum of the base transaction cost (21000) plus the function execution cost (15000), which equals 36000.

❓ Predict Output

advanced

Bitcoin Transaction Fee Calculation

What is the transaction fee if a Bitcoin transaction size is 250 bytes and the fee rate is 50 satoshis per byte?

Blockchain / Solidity

tx_size_bytes = 250
fee_rate_sat_per_byte = 50
fee = tx_size_bytes * fee_rate_sat_per_byte
print(fee)

A 5000

B 50

C 12500

D 250

💡 Hint

Multiply the size by the fee rate.

The fee is calculated by multiplying the transaction size (250 bytes) by the fee rate (50 satoshis/byte), resulting in 12500 satoshis.

🧠 Conceptual

advanced

Consensus Mechanism Difference

Which consensus mechanism does Ethereum currently use compared to Bitcoin?

A Both use Proof of Work.

B Ethereum uses Proof of Work, Bitcoin uses Proof of Stake.

C Both use Proof of Stake.

D Ethereum uses Proof of Stake, Bitcoin uses Proof of Work.

💡 Hint

Ethereum recently changed its consensus method.

Ethereum transitioned to Proof of Stake to reduce energy consumption, while Bitcoin still uses Proof of Work.

🧠 Conceptual

expert

Smart Contract Language Difference

Which programming language is primarily used for writing Ethereum smart contracts, and what is Bitcoin's scripting language characteristic?

A Ethereum uses Python, Bitcoin uses Solidity.

B Ethereum uses Solidity, Bitcoin uses a non-Turing complete scripting language.

C Ethereum uses JavaScript, Bitcoin uses Python.

D Ethereum uses C++, Bitcoin uses Java.

💡 Hint

Ethereum smart contracts are written in a special language designed for it.

Ethereum smart contracts are mainly written in Solidity, a Turing-complete language. Bitcoin uses a simpler, non-Turing complete scripting language for security.

Practice

1. Which of the following best describes the primary purpose of Bitcoin compared to Ethereum?

easy

A. Bitcoin is mainly digital cash, while Ethereum supports programmable contracts.

B. Bitcoin is used for smart contracts, Ethereum is only for money transfer.

C. Bitcoin and Ethereum have the same purpose and features.

D. Ethereum is only a digital currency, Bitcoin is a platform for apps.

Solution

1. Step 1: Understand Bitcoin's main use

   Bitcoin is designed primarily as digital money for simple transfers.

2. Step 2: Understand Ethereum's main use

   Ethereum allows programmable smart contracts and decentralized apps beyond just money.

3. Final Answer:

   Bitcoin is mainly digital cash, while Ethereum supports programmable contracts. -> Option A

4. Quick Check:

   Bitcoin = digital cash, Ethereum = programmable blockchain [OK]

Hint: Bitcoin = money; Ethereum = apps and contracts [OK]

Common Mistakes:

• Confusing Ethereum as only digital money
• Thinking Bitcoin supports smart contracts
• Believing both have identical features

2. Which syntax correctly describes Ethereum's smart contract language?

easy

A. Ethereum smart contracts are written in Python.

B. Ethereum smart contracts are written in Solidity.

C. Ethereum smart contracts use SQL queries.

D. Ethereum smart contracts are written in HTML.

Solution

1. Step 1: Identify Ethereum's contract language

   Ethereum smart contracts are mainly written in Solidity, a language designed for this purpose.

2. Step 2: Eliminate incorrect languages

   Python, SQL, and HTML are not used for Ethereum smart contracts.

3. Final Answer:

   Ethereum smart contracts are written in Solidity. -> Option B

4. Quick Check:

   Solidity = Ethereum contract language [OK]

Hint: Solidity is Ethereum's contract language [OK]

Common Mistakes:

• Confusing Solidity with Python
• Thinking SQL or HTML are contract languages
• Assuming Bitcoin uses Solidity

3. What will be the output of this code snippet describing Bitcoin and Ethereum usage?

bitcoin_use = 'money transfer'
ethereum_use = 'smart contracts'
print(f'Bitcoin is for {bitcoin_use}, Ethereum is for {ethereum_use}.')

medium

A. Bitcoin is for mining, Ethereum is for trading.

B. Bitcoin is for smart contracts, Ethereum is for money transfer.

C. Bitcoin is for money transfer, Ethereum is for smart contracts.

D. Bitcoin and Ethereum have no specific uses.

Solution

1. Step 1: Read variable assignments

   bitcoin_use is set to 'money transfer', ethereum_use is set to 'smart contracts'.

2. Step 2: Understand the print statement

   The print outputs the string with these variables inserted in the correct places.

3. Final Answer:

   Bitcoin is for money transfer, Ethereum is for smart contracts. -> Option C

4. Quick Check:

   Variables match output text [OK]

Hint: Match variables to output placeholders [OK]

Common Mistakes:

• Swapping bitcoin_use and ethereum_use values
• Misreading the print format
• Ignoring variable values

4. Find the error in this statement about Bitcoin and Ethereum:

"Bitcoin supports complex smart contracts, Ethereum only supports simple transactions."

medium

A. Bitcoin does not support complex smart contracts; Ethereum does.

B. Ethereum does not support any transactions.

C. The statement is correct as is.

D. Bitcoin and Ethereum both only support simple transactions.

Solution

1. Step 1: Analyze Bitcoin's capabilities

   Bitcoin mainly supports simple transactions, not complex smart contracts.

2. Step 2: Analyze Ethereum's capabilities

   Ethereum supports complex smart contracts and decentralized applications.

3. Final Answer:

   Bitcoin does not support complex smart contracts; Ethereum does. -> Option A

4. Quick Check:

   Bitcoin = simple transactions, Ethereum = complex contracts [OK]

Hint: Remember Bitcoin is simple money, Ethereum is programmable [OK]

Common Mistakes:

• Thinking Bitcoin supports complex contracts
• Believing Ethereum only does simple transfers
• Assuming both have same features

5. You want to build a decentralized app that automatically executes agreements when conditions are met. Which blockchain should you choose and why?

hard

A. Ethereum, because it only supports simple money transfers.

B. Bitcoin, because it has the fastest transaction speed for apps.

C. Bitcoin, because it supports complex programmable contracts.

D. Ethereum, because it supports programmable smart contracts for automation.

Solution

1. Step 1: Identify app requirements

   The app needs automatic execution of agreements, which means programmable logic is required.

2. Step 2: Match blockchain capabilities

   Ethereum supports programmable smart contracts enabling automation; Bitcoin does not.

3. Final Answer:

   Ethereum, because it supports programmable smart contracts for automation. -> Option D

4. Quick Check:

   Programmable contracts = Ethereum [OK]

Hint: Choose Ethereum for programmable apps [OK]

Common Mistakes:

• Choosing Bitcoin for smart contract apps
• Confusing transaction speed with programmability
• Ignoring Ethereum's contract features